C r ist i na Nanni – Stef ano Fant i PET-CT: Rare Findings and Diseases
C ri s ti n a N a n n i – Ste f a n o Fant i
PET-CT: Rare Findings and Diseases
Dr. Cristina Nanni Ospedale S. Orsola-Malpighi Dept. of Nuclear Medicine Via Massarenti 9 40138 Bologna Italy
[email protected]
ISBN: 978-3-642-24698-2
Prof. Dr. Stefano Fanti Univ. Bologna Policlinico S.Orsola-Malpighi Dipto. Medicina Nucleare Via Massarenti 40100 Bologna Italy
[email protected]
e-ISBN: 978-3-642-24699-9
DOI: 10.1007/978-3-642-24699-9 Library of Congress Control Number: 2012931509 © 2012 Springer-Verlag Berlin Heidelberg This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilm or in any other way, and storage in data banks. Duplication of this publication or parts thereof is permitted only under the provisions of the German Copyright Law of September 9, 1965, in its current version, and permission for use must always be obtained from Springer. Violations are liable to prosecution under the German Copyright Law. The use of general descriptive names, registered names, trademarks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. Product liability: The publishers cannot guarantee the accuracy of any information about dosage and application contained in this book. In every individual case the user must check such information by consulting the relevant literature. Printed on acid-free paper Springer is part of Springer Science + Business Media (www.springer.com)
Acknowledgments
Cristina Nanni would like to thank Prof. Stefano Fanti for his trust and brilliant vision in the field of PET imaging and the staff of the PET Centre in Bologna (particularly Dr. Vincenzo Allegri, Dr. Paolo Castellucci, Dr. Giancarlo Montini, Dr. Valentina Ambrosini and all the residents) for great work and help in documenting interesting cases. She also thanks Riccardo and Francesca, mum and dad, for a great patience, practical support and constant encouragement. Stefano Fanti would like to thank Dr. Cristina Nanni for her expertise, dedication and attitude: indeed she did all the work, and not only concerning the present book. He also thanks Maddalena, Raffaele and Anita for the great daily joy.
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Contents
Chapter 1
FDG: Rare Diseases
Chapter 2
11C-Choline: Rare Diseases
Chapter 3
11C-Methionine: Rare Diseases
Chapter 4
68Ga-Somatostatine Analogs: Rare Diseases
Chapter 5
FDG: Rare Findings
Chapter 6
11C-Choline: Rare Findings
Chapter 7
68Ga-Somatostatine Analogs: Rare Findings
Index
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137
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151
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159
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265
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283
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vii
Introduction
Positron Emission Tomography (PET) is an emerging functional imaging technique particularly useful in the diagnostic flow chart of oncological patients. FDG is by far the most employed tracer, providing high accuracy for the detection of most malignancies. Other emerging tracers proven to have a significant impact on patient management are 11C-methionine, 11C-choline and 68Ga-somatostatine analogues. The increasing use of integrated functional (PET) and morphological (CT) imaging and the growing number of patients undergoing these procedures lead to the need for a great deal of experience in image interpretation, since incidental findings and comorbidities can cause misreading of images. This can also be enhanced by the nonspecificity of FDG and, to a lesser extent, other tracers. In these cases, experience, complete patient clinical history and interpretation of co-registered CT images can be crucial for providing correct results to clinicians and for reaching conclusive reports, which are usually expected from a second level imaging procedure such as PET/CT. The aim of this atlas is, therefore, to provide concrete help for reading PET/CT images, presenting several cases characterized by unusual (but still quite common) incidental findings that can come to the attention of PET doctors during routine practice. Cases of rare diseases evaluated with PET are also included, in consideration of the constantly increasing number of clinical indications for PET imaging. Each case is briefly described in a few lines, and the PET result is clarified with multiple images including MIP. In addition, axial, sagittal and coronal sections of CT and fused images centered on the finding of interest are provided. Furthermore, a brief description of the pathological condition under evaluation is reported, including references from the scientific literature when necessary. In conclusion, this atlas is aimed at helping physicians read PET/CT scans in their daily clinical practice. In our experience the key reason for a successful relationship with referring clinicians is reports of outstanding quality. This requires great expertise, but also the capability of recognizing unusual findings, as well as the knowledge of uncommon diseases that may be evaluated by PET scans. Our goal was to provide practical support for such situations.
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Chapter 1
FDG: Rare Diseases
Case 1
Clinical Diagnosis: Giant Cell Tumor (GCT) . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4
Clinical Diagnosis: Pulmonary Amyloidosis . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6
Cases 3–4
Clinical Diagnosis: Pneumoconiosis . . . . .
8
Case 5
Clinical Diagnosis: Pulmonary Aspergillosis . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12
Clinical Diagnosis: Pulmonary Scar Cancer . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
14
Clinical Diagnosis: HIV-Related Pneumonia . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
16
Clinical Diagnosis: Pulmonary Sarcoidosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
18
Clinical Diagnosis: Varicella Pneumonia . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
20
Clinical Diagnosis: Castleman’s Disease . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
22
Clinical Diagnosis: Perivalvular Abscess . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
24
Case 12
Clinical Diagnosis: Hepatic Abscess . . . . .
26
Case 13
Clinical Diagnosis: Pediatric Hepatic Hilar Abscess . . . . . . . . . . . . . . . . . . . . . . . . . . .
28
Clinical Diagnosis: Basal-Cell Carcinoma . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
30
Clinical Diagnosis: Graves-Basedow Disease . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
32
Case 2
Case 6
Case 7
Case 8
Case 9
Case 10
Case 11
Case 14
Case 15
C. Nanni, S. Fanti, PET-CT: Rare Findings and Diseases, DOI 10.1007/978-3-642-24699-9_1, © Springer-Verlag Berlin Heidelberg 2012
1
1
2
FDG: Rare Diseases
Case 16
Clinical Diagnosis: Erysipelas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
34
Case 17
Clinical Diagnosis: Initial Stage Discitis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
36
Case 18
Clinical Diagnosis: Erdheim-Chester Disease . . . . . . . . . . . . . . . . . . . . . . . . . .
38
Case 19
Clinical Diagnosis: Necrotizing Fasciitis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
40
Case 20
Clinical Diagnosis: Vaquez Disease . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
42
Case 21
Clinical Diagnosis: Peritoneal Catheter Infection . . . . . . . . . . . . . . . . . . . . . .
44
Case 22
Clinical Diagnosis: Implantable Cardiac Device Infection . . . . . . . . . . . . . .
46
Case 23
Clinical Diagnosis: Thoracic Aortic Graft Infection . . . . . . . . . . . . . . . . . . . . .
48
Case 24
Clinical Diagnosis: Rheumatoid Arthritis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
50
Case 25
Clinical Diagnosis: Idiopathic Mediastinal Fibrosis . . . . . . . . . . . . . . . . . . . . .
52
Case 26
Clinical Diagnosis: Spinal Disc Herniation . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
54
Case 27
Clinical Diagnosis: Mesenteritis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
56
Case 28
Clinical Diagnosis: Osteomyelitis of the Foot . . . . . . . . . . . . . . . . . . . . . . . . . .
58
Case 29
Clinical Diagnosis: Peritoneal Mesothelioma . . . . . . . . . . . . . . . . . . . . . . . . . .
60
Case 30
Clinical Diagnosis: Lymphoma of the Brain . . . . . . . . . . . . . . . . . . . . . . . . . . . .
62
Case 31
Clinical Diagnosis: Pilonidal Cyst . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
64
Cases 32–33
Clinical Diagnosis: Osteomyelitis of the Sternum . . . . . . . . . . . . . . . . . . . . . .
66
Cases 34–35
Clinical Diagnosis: Paget’s Disease . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
70
Cases 36–38
Clinical Diagnosis: Postsurgical Bone Infection . . . . . . . . . . . . . . . . . . . . . . . .
74
Cases 39–40
Clinical Diagnosis: Pigmented Villonodular Synovitis . . . . . . . . . . . . . . . . . .
78
Case 41
Clinical Diagnosis: Vascular Graft Infection . . . . . . . . . . . . . . . . . . . . . . . . . . . .
82
Case 42
Clinical Diagnosis: Atrial Sarcoma . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
84
Case 43
Clinical Diagnosis: Avascular Necrosis of Bones . . . . . . . . . . . . . . . . . . . . . . . .
86
Case 44
Clinical Diagnosis: Malignant Otitis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
88
Case 45
Clinical Diagnosis: Bone Sarcoidosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
90
1
FDG: Rare Diseases
Case 46
Clinical Diagnosis: Polydermatomyositis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
92
Case 47
Clinical Diagnosis: RS3PE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
94
Cases 48–49
Clinical Diagnosis: Tuberculosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
96
Case 50
Clinical Diagnosis: Sacroiliitis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
100
Case 51
Clinical Diagnosis: Pulmonary MALT Lymphoma. . . . . . . . . . . . . . . . . . . . . . .
102
Case 52
Clinical Diagnosis: Fibrosarcoma . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
104
Case 53
Clinical Diagnosis: Large Soft Tissue Sarcoma . . . . . . . . . . . . . . . . . . . . . . . . .
106
Case 54
Clinical Diagnosis: Stump Appendicitis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
108
Case 55
Clinical Diagnosis: Bowel Transplantation with EBV Infection . . . . . . . . . .
110
Case 56
Clinical Diagnosis: Von Recklinghausen Disease . . . . . . . . . . . . . . . . . . . . . . .
112
Case 57
Clinical Diagnosis: Wilms’ Tumor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
114
Case 58
Clinical Diagnosis: Microcystic Tumor of the Pancreas . . . . . . . . . . . . . . . . .
116
Cases 59–60
Clinical Diagnosis: Epilepsy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
118
Case 61
Clinical Diagnosis: Spindle Cell Carcinoma of the Prostate . . . . . . . . . . . . .
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Suggested Reading. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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3
1
Case 1
Clinical Diagnosis: Giant Cell Tumor (GCT)
⊡ Fig. 1.1 FDG PET/CT demonstrated several positive areas. A differential diagnosis between infection and tumor persistence was not possible
4
⊡ Fig. 1.2 FDG PET/CT demonstrated persistence of positive areas, increased in terms of extension. The final diagnosis was tumor in local progression
Case 1 Clinical Diagnosis: Giant Cell Tumor (GCT)
1
⊡ Giant Cell Tumor Clinical Case GCT is a locally destructive, benign and monostotic tumoral lesion, typically presenting in the metaepiphysis of long tubular bones. Although defined as a benign lesion, adjacent soft tissue invasion, angiovascular invasion and pulmonary metastases may occur. The exact origin is still unknown, but it seems that the “stromal” cell, or mononuclear spindle cell, is neoplastic. This tumor represents 8% of all primary and approximately 20% of benign primary bone tumors. It mostly affects adults in the third, fourth and fifth decades of life (72%). There is a slight female predominance. Clinically, the patient presents with pain of several weeks to months’ duration and a constantly expanding mass on X-ray, primarily in the epiphysis, leading to cortex destruction, pathological fracture and soft tissue invasion. Finally, ulceration of the skin occurs if not threatened. Surgical intervention is the only treatment of choice. Nontreatment always leads to destruction of cortical bone, soft tissue invasion and finally ulceration of the skin. Local recurrences can occur following proper treatment, mostly indicating less radical initial resection. The prognosis is generally good, despite recurrences and pulmonary metastases. In general, much depends on the surgical technique and expertise in combination with the histological grade of this tumor. Although pulmonary metastases may occur in rare cases, angiovascular invasion does not have any significant influence on its prognosis. The mortality rate is about 4%.
A 50-year-old male patient was affected by Paget’s disease of the pelvis and spine. He developed a giant cell tumor involving the L2 to L4 vertebrae. He was operated on to remove the disease. Three months after surgery he noticed enlarged left inguinal nodes that turned out to be inflammatory after the biopsy. Inflammation markers were moderately increased. He was referred for an FDG PET/CT scan to exclude postsurgical vertebral infection (Fig. 1.1). The patient underwent 2-month antibiotic therapy and a second FDG PET/CT control (Fig. 1.2). The final diagnosis was tumor in local progression.
5
1
Case 2
Clinical Diagnosis: Pulmonary Amyloidosis
a
b
6
⊡ Fig. 2.1 FDG PET/CT (a: MIP image) was negative for bone myelomatous lesions, but demonstrated several positive areas in both lungs with SUV max = 11. Those hypermetabolic areas
c
corresponded to consolidative changes on CT images (b: chest CT, c: corresponding fused images)
Case 2 Clinical Diagnosis: Pulmonary Amyloidosis
⊡ Amyloidosis Associated to Multiple Myeloma Primary amyloidosis is a condition characterized by deposition of amyloid protein comprising immunoglobulin light chains usually in multiple organs (heart, kidney, liver, and peripheral or autonomic nervous system). More than 80% of cases are associated with monoclonal gammopathy, and hence amyloidosis can be considered a form of plasma cell dyscrasia. In patients with multiple myeloma, clinically evident amyloidosis develops in 10–15% of patients. Pulmonary amyloidosis may be organrestricted or part and parcel of systemic amyloidosis. Pulmonary amyloidosis may present as pulmonary nodules, endobronchial amyloid plaques, diffuse interstitial amyloidosis or pleural effusion with pleural amyloid deposition. Pleural amyloid plaques and diffuse interstitial amyloidosis are usually associated with systemic amyloidosis, while endobronchial amyloid plaques are an organ-restricted type of amyloidosis not associated with systemic amyloidosis. Symptoms depend on the site, extent and pattern of amyloid deposit. In systemic amyloidosis, pulmonary symptoms are usually due to concurrent restrictive amyloid cardiomyopathy instead of the pulmonary amyloid deposition. On the other hand, endobronchial amyloidosis results in bronchial or tracheal stenosis and thus the corresponding symptoms of cough, wheeze, hemoptysis or recurrent respiratory infections.
1
Clinical Case A 61-year-old male patient was affected by multiple myeloma. After therapy, he developed unclear bilateral pulmonary shadows at chest X-ray. Chest CT demonstrated bilateral consolidative changes. His clinical presentation was unremarkable. He did not have any pulmonary symptoms of cough, sputum production or hemoptysis, nor did he have systemic symptoms such as fever, general body malaise or weight loss. Multiple myeloma was clinically in complete remission. He was referred for an FDG PET/CT scan to assess the response to therapy (Fig. 2.1). Subsequently, he underwent a pulmonary biopsy, which turned out to be positive for pulmonary amyloidosis.
7
1
Cases 3–4 Clinical Diagnosis: Pneumoconiosis
a
b
c
8
⊡ Fig. 3.1 FDG PET/CT (a: MIP image) was negative for cancer relapse but demonstrated several positive areas in both lungs (white arrows on c) with SUV max = 7, spleen enlargement and hypermetabolism, and multiple
hypermetabolic lymph nodes. In the chest, the hypermetabolic areas corresponded to multiple nodules and fibrotic areas (white arrows on b) on CT images (b: chest CT, c: corresponding fused images)
Cases 3–4 Clinical Diagnosis: Pneumoconiosis
1
⊡ Pneumoconiosis Clinical Case 3 Pneumoconiosis is a bronchoscopic finding characterized by the development of dark pigments on the airways and bronchial mucosa. They can result in bronchial damage, metamorphosis and obliteration. Pathologically, these damages appear as a result of sedimentation of silica, carbon and asbestos particles in the cytoplasm of mucosal and submucosal cells as well as macrophages. A chest high-resolution CT through the upper lobes showed bilateral progressive mass fibrosis with a few nodules around the lesions. A further conglomeration of nodules also can be present in the lower lobes. FDG PET/CT images show increased uptake in pulmonary lesions, indistinguishable from that of lung cancer. There also may be increased uptake in the bilateral hilar and left supraclavicular lymph nodes. Treatment for coal worker’s pneumoconiosis is palliative and preventive.
A 75-year-old male smoker, a train operator, was affected by colon cancer, which was radically treated with surgery and chemotherapy. Two years after therapy, he was referred for an FDG PET/ CT scan because of increasing levels of tumoral serum markers (Fig. 3.1). FDG PET/CT did not demonstrate a disease relapse, but hypermetabolic bilateral pulmonary areas were detected. The patient subsequently underwent a chest CT and BAL. Both were consistent with pneumoconiosis (anthracosis).
9
1
Cases 3–4 Clinical Diagnosis: Pneumoconiosis
a
b
10
⊡ Fig. 4.1 FDG PET/CT (a: MIP image) was negative for cancer relapse but demonstrated several positive areas in both lungs with SUV max = 6 (white arrows on c). In the chest, the
c
hypermetabolic areas corresponded to multiple nodules and fibrotic areas (white arrows on b) on CT images (b: chest CT, c: corresponding fused images)
Cases 3–4 Clinical Diagnosis: Pneumoconiosis
1
Clinical Case 4 A 61-year-old female patient who smoked was affected by DLCL (diffuse large cell lymphoma). During the follow-up, an FDG PET/CT was performed, demonstrating persistent complete remission (Fig. 4.1) but increased pulmonary bilateral uptake. The patient subsequently underwent a chest CT and BAL. Both were consistent with pneumoconiosis (silicosis).
11
1
Case 5
Clinical Diagnosis: Pulmonary Aspergillosis
a
b
c
12
⊡ Fig. 5.1 FDG PET/CT (a: MIP image) was positive for lymphoma (bilateral inguinal hypermetabolic lymph nodes and spleen). The hypermetabolic area in the left lung (white arrow on c,
SUV max 8) corresponded, at CT images, to an area of consolidation and surrounding groundglass opacity (white arrow on b) in the left upper lobe (b: chest CT, c: corresponding fused images)
Case 5
Clinical Diagnosis: Pulmonary Aspergillosis
1
⊡ Aspergillosis Clinical Case Aspergillosis refers to the spectrum of diseases caused by Aspergillus species. The pulmonary manifestations range from noninvasive diseases, such as the presence of a fungal ball (aspergilloma), or an allergic response responsible for the syndrome of allergic bronchopulmonary aspergillosis (ABPA), to semi-invasive or invasive infections. Aspergillus species enter the host most commonly through the lungs by the inhalation of conidia. Invasive aspergillosis is thus a major cause of morbidity and mortality in immunosuppressed patients. Without effective host defenses following pulmonary exposure, the conidia resting in the alveoli begin to enlarge and germinate. Hyphal transformation with vascular invasion and dissemination of infection is a potential sequela. The incidence of infection with Aspergillus has increased in recent years, primarily because of the increasing number of immunosuppressed patients encountered in clinical practice (solid organ and bone marrow transplantation, corticosteroids and immune-modulating drugs, and the epidemic of infection with the human immunodeficiency virus, HIV). Established infection in these patients still leads to a significant mortality.
A 37-year-old male had HIV infection. This patient was affected by HIV-related lymphoma, radically treated with chemotherapy. After therapy he presented with fever and was diagnosed with pulmonary aspergillosis on the basis of the chest CT results and clinical symptoms. The patient was referred for an FDG PET/CT to exclude lymphoma persistence (Fig. 5.1).
13
1
Case 6
Clinical Diagnosis: Pulmonary Scar Cancer
a
b
c
14
⊡ Fig. 6.1 FDG PET/CT (a: MIP image) demonstrated an area of increased tracer uptake (SUV max 9, white arrow on c) corresponding to a suspicious right pulmonary subpleural nodule
(white arrow on b) (b: chest CT, c: corresponding fused images). This was consistent with malignancy, subsequently identified as lung scar cancer
Case 6 Clinical Diagnosis: Pulmonary Scar Cancer
1
⊡ Pulmonary Scar Cancer Clinical Case Lung scar carcinoma (SC) was first described by Friedrich in 1939 as a type of lung cancer that originates around peripheral scars in the lung. Scarring in the lung can result from a variety of infections, injuries and lung diseases. Scars can also be due to repeated episodes of tumor necrosis and healing. SCs are typically found as subpleural adenocarcinomas with retraction or puckering of the overlying pleura. The presence of type III collagen and an extracellular matrix suggests an ongoing fibrosing process secondary to the host response to the neoplasm. The high concentration of type III collagen in SC indicates that the fibrous tissue is in an active immature state compared with nonelastic fibrous tissue, which is mature and contains type I and type V collagen, that is usually found in scars or fibrotic areas.
A 77-year-old female, who was a smoker, was affected by severe smoke-related paraseptal and centralobular emphysema. For this reason she underwent a routine chest CT, highlighting a right small pulmonary subpleural nodule. She was referred for an FDG PET/CT to characterize the nodule; the results were positive (Fig. 6.1). Subsequently, she underwent a CT-guided biopsy. Histopathology indicated adenocarcinoma. After surgery, the diagnosis was pulmonary scar cancer.
15
1
Case 7
Clinical Diagnosis: HIV-Related Pneumonia
a
b
c
16
⊡ Fig. 7.1 FDG PET/CT (a: MIP image) demonstrated a large area of increased tracer uptake (white arrow on c, SUV max 23) involving the upper lobe of the left lung and small multiple hypermetabolic areas in the upper lobe of the
right lung, corresponding to consolidative areas at chest CT (white arrow on b) (b: chest CT, c: corresponding fused images). This was consistent with pneumonia. No lymphoma-related areas were detected
Case 7 Clinical Diagnosis: HIV-Related Pneumonia
1
⊡ HIV-Related Pneumonia Clinical Case HIV-related pneumonia is among the most frequent life-threatening infectious complications in immunocompromised patients. The agents responsible for this infection are many. The most frequent kinds of pneumonia are fungal pneumonia, pneumonias from cytomegalovirus (CMV) and Pneumocystis jirovecii. In recipients of hematopoietic cell transplantations (HCT), the incidence of CMV is 20–35%, and the mortality is up to 50%. The incidence of pneumonia in AIDS patients is estimated to be over 50%, where it is the most common opportunistic infection. Depending on the underlying disease, mortality lies between 20% and 50%. Independent from the underlying disease, the clinical presentation in both cases is fever, dyspnea, unproductive coughing and uncharacteristic reduced transparency in conventional thorax images. For detecting and differentiating pneumonia in immunocompromised patients, thin-section CT of the thorax is the imaging modality of choice.
A 45-year-old male patient with HIV infection was affected by HIV-related lymphoma, which was radically treated with chemotherapy. After therapy he presented with fever and was diagnosed with pneumonia on the basis of chest CT results and clinical symptoms. The patient was referred for an FDG PET/CT to exclude persistence of the lymphoma (Fig. 7.1).
17
1
Case 8
Clinical Diagnosis: Pulmonary Sarcoidosis
a
b
c
d
⊡ Fig. 8.1 FDG PET/CT (a: MIP image) demon18
strated an area of increased tracer uptake (SUV max 15) in L3 (b: chest CT, c: corresponding fused images) and a large area of increased tracer uptake involving both lungs correspond-
e
ing to consolidative areas, bronchial distortion and bronchovascular deformation at chest CT (d: chest CT, e: corresponding fused images). This was consistent with active sarcoidosis
Case 8 Clinical Diagnosis: Pulmonary Sarcoidosis
1
⊡ Sarcoidosis Clinical Case Sarcoidosis is a multiorgan granulomatous disease of unknown cause that occurs in mediastinal and pulmonary sites in 90% of cases. The clinical course varies widely. Parenchymal abnormalities often resolve spontaneously, but they evolve toward pulmonary fibrosis in 20–25% of cases. The course of pulmonary sarcoidosis has been widely studied using clinical, chest radiographic and pulmonary function follow-up. The presence of pulmonary fibrosis (in stage IV sarcoidosis) on a chest radiograph is generally associated with poor pulmonary function and a poor prognosis with increased morbidity and mortality. Although the chest radiographic findings of pulmonary fibrosis show some correlation with irreversible disease and insensitivity to corticosteroids, no close correlation exists between the chest radiographic staging and histopathology or pulmonary function. The high concentration of type III collagen in SC indicates that the fibrous tissue is in an active immature state compared with nonelastic fibrous tissue, which is mature and contains type I and type V collagen, that is usually found in scars or fibrotic areas.
A 33-year-old female patient presented with dyspnea and underwent a chest X-ray and chest CT. CT scan revealed a bronchial distortion pattern with bronchovascular deformation consistent with pulmonary sarcoidosis. The patient was referred for an FDG PET/CT demonstrating pulmonary bilateral uptake and bone uptake (Fig. 8.1). This was consistent with active sarcoidosis.
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1
Case 9
Clinical Diagnosis: Varicella Pneumonia
a
b
c
20
⊡ Fig. 9.1 FDG PET/CT (a: MIP image) demonstrated an area of increased tracer uptake (white arrows on c, SUV max 3) demonstrating mild
uptake in the small pulmonary nodules (white arrows on b) (b: CT scan; c: fused images)
Case 9
Clinical Diagnosis: Varicella Pneumonia
1
⊡ Varicella Pneumonia Clinical Case Varicella (chickenpox) is a common infection of childhood typically affecting children aged 2–8 years old and usually follows a benign outcome. However, data from Europe and North America have shown that the incidence of chickenpox in adults has doubled in recent years, and this has been paralleled with an increase in hospital admissions and mortality. The reason for this age shift is not known, though it may be the result of less exposure to the Varicella zoster virus (VZV), smaller family size or increased virus virulence. Varicella pneumonia is the most common and serious complication of chickenpox infection in adults with a reported incidence in healthy adults that is 25-fold greater than in children. Currently, the proportion of adults in industrial nations susceptible to chickenpox is ~7%, evident from negative Varicella zoster antibodies. Varicella pneumonia is so uncommon that large-scale studies are difficult to conduct, and most published studies represent either collections of small case series or retrospective analyses over many years.
A 26-year-old female patient treated for HD 2 years before presented with a 5-day history of cough, fever and mild dyspnea. Chest radiography showed multiple small nodules in both lungs. Chest computed tomography revealed numerous ill-defined nodules 1–5 mm in diameter. Her 3-year-old son had recently had chickenpox. The diagnosis was varicella pneumonia. The patient was referred for an FDG PET/CT during the follow-up for lymphoma, demonstrating mild uptake in the small pulmonary nodules (Fig. 9.1). This was consistent with varicella pneumonia.
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1
Case 10 Clinical Diagnosis: Castleman’s Disease
a
b
c
22
⊡ Fig. 10.1 FDG PET/CT (a: MIP image) demonstrated multiple areas of increased tracer uptake (SUV max 18) in laterocervical, axillary, mediastinal and abdominal lymph nodes, associated
with hypermetabolism in the spleen (b: CT scan; c: fused images) and L5 consistent with Castleman’s disease
Case 10 Clinical Diagnosis: Castleman’s Disease
1
⊡ Castleman’s Disease Clinical Case Castleman’s disease is a very rare disorder characterized by noncancerous growths (tumors) that may develop in the lymph node tissue at a single site or throughout the body. It involves hyperproliferation of certain B cells that often produce cytokines. While not officially considered a cancer, the overgrowth of lymphocytes with this disease is similar to lymphoma. The most common “B symptoms” of MCD are high fever, anemia, weight loss, loss of appetite and low white blood cell counts, which may to be due to the overproduction of interleukin 6. Symptomatically, therefore, MCD can be difficult to diagnose, and even in the case of lymph node biopsy, a conclusive diagnosis remains problematic. Castleman’s disease is seen in POEMS syndrome and is implicated in 10% of cases of paraneoplastic pemphigus.
A 47-year-old male patient presented with fever, and cervical and axillary lymph node enlargement. He underwent a biopsy indicating the diagnosis of Castleman’s disease. The patient was referred for an FDG PET/CT to stage the disease before therapy (Fig. 10.1).
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1
Case 11 Clinical Diagnosis: Perivalvular Abscess
a
b
24
⊡ Fig. 11.1 FDG PET/CT (a: MIP image) demonstrated a focal area of increased tracer uptake (white arrow on c, SUV max 5) closed to the
c
mitral prosthesis (white arrow on b) (b: CT scan; c: fused images) consistent with perivalvular abscess
Case 11 Clinical Diagnosis: Perivalvular Abscess
1
⊡ Perivalvular Abscess Clinical Case Perivalvular abscess is a known and feared complication of left-sided endocarditis because it is associated with increased mortality. It appears to occur more often with prosthetic valve endocarditis than with native valve endocarditis, and it appears to be more common when the pathogen is Staphylococcus aureus than when viridans group streptococci are the infecting organisms. The advent of transesophageal echocardiography has markedly improved the diagnostic sensitivity of echocardiography for infective endocarditis in general and perivalvular abscess in particular. In the largest series of perivalvular abscesses reported, the sensitivity of transesophageal echocardiography for detecting perivalvular abscess was 80%, as compared with only 36% for transthoracic echocardiography.
A 61-year-old male patient presented with fever and an increase in inflammation serum marker levels. Imaging procedures such as whole body CT, abdominal US, white blood cell scintigraphy and transvalvular cardiac ultrasound were negative. The patient was referred for an FDG PET/CT demonstrating an area of increased tracer uptake close to the mitral prosthesis (Fig. 11.1). This was consistent with perivalvular abscess that was confirmed at transesophageal US 14 days later.
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Case 12 Clinical Diagnosis: Hepatic Abscess
a
b
c
26
⊡ Fig. 12.1 FDG PET/CT (a: MIP image) demonstrated a focal area of increased tracer uptake (SUV max 9) in the liver (b: CT scan; c: fused
images) consistent with hepatic abscess. At CT scan the presence of several cystic areas complicates the image interpretation
Case 12 Clinical Diagnosis: Hepatic Abscess
1
⊡ Hepatic Abscess Clinical Case A liver abscess occurs when bacteria or protozoa destroy hepatic tissue, producing a cavity, which fills with infectious organisms, liquelled liver cells and leukocytes. Necrotic tissue then walls off the cavity from the rest of the liver. Liver abscess occurs equally in men and women, usually in those over age 50. Death occurs in 15% of affected patients despite treatment. Underlying causes include benign or malignant biliary obstruction along with cholangitis, extrahepatic abdominal sepsis, and trauma or surgery to the right upper quadrant. Liver abscesses also occur from intra-arterial chemoembolizations or cryosurgery in the liver, which causes necrosis of tumor cells and potential infection. Common signs include abdominal pain, weight loss, fever, chills, diaphoresis, nausea, vomiting and anemia. Signs of right pleural effusion, such as dyspnea and pleural pain, develop if the abscess extends through the diaphragm. Liver damage may cause jaundice. Ultrasonography and computed tomography (CT) scan with contrast medium can accurately define intrahepatic lesions. Percutaneous needle aspiration of the abscess can also be performed with diagnostic tests to identify the causative organism. Antibiotic therapy, along with drainage, is the preferred treatment for most hepatic abscesses.
A 68-year-old female patient with chronic renal failure due to polycystic kidney disease presented with fever and an increase in inflammation serum marker levels. Results of imaging procedures such as whole body CT and abdominal US were negative, and the interpretation was complicated by the presence of several large kidney and liver cysts. The patient was referred for an FDG PET/CT demonstrating an area of increased tracer uptake in the liver (Fig. 12.1). This was consistent with an abscess, which was subsequently treated with antibiotics.
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Case 13 Clinical Diagnosis: Pediatric Hepatic Hilar Abscess
a
b
c
28
⊡ Fig. 13.1 FDG PET/CT (a: MIP image) demonstrated two focal areas of increased tracer uptake (white arrows on c, SUV max 8.7) in the liver hilum (b: CT scan; c: fused images) consistent with abscess
Case 13
Clinical Diagnosis: Pediatric Hepatic Hilar Abscess
1
⊡ Pediatric Hepatic Hilar Abscess Clinical Case Cystic liver lesions in septic children represent liver abscesses, pyogenic or amebic, which are frequently fatal if not diagnosed early and treated appropriately. Ultrasonography and computed tomography have simplified the diagnosis and treatment of these diseases, but a high index of suspicion is required because the signs and symptoms of liver abscess in children are nonspecific. Antibiotic therapy, along with drainage, is the preferred treatment for most hepatic abscesses.
A 5-year-old male patient presented with fever and an increase in serum inflammatory marker levels. Results of imaging procedures such as whole body CT and abdominal US were negative. The patient was referred for an FDG PET/CT demonstrating two areas of increased tracer uptake in the liver hilum (Fig. 13.1). This was consistent with an inflammatory process or with a malignancy. The patient underwent surgery, confirming the presence of a hepatic hilar abscess.
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Case 14 Clinical Diagnosis: Basal-Cell Carcinoma
a
b
c
30
⊡ Fig. 14.1 FDG PET/CT (a: MIP image) demonstrated several focal areas of increased tracer uptake (SUV max 13) involving the left hemith-
orax (b: CT scan; c: fused images) and, to a lesser extent, the right hemithorax, consistent with basal cell carcinoma relapse
Case 14 Clinical Diagnosis: Basal-Cell Carcinoma
1
⊡ Basal Cell Carcinoma Clinical Case Basal cell carcinoma (BCC) is the most common skin cancer in humans, yet it accounts for less than 0.1% of patient deaths due to cancer. Basal cell skin cancer tumors typically appear on sunexposed skin, are slow growing and rarely metastasize (0.028–0.55%). BCC usually appears as a flat, firm, pale area that is small, raised, pink or red, translucent, shiny and waxy, and the area may bleed following minor injury. Tumor size can vary from a few millimeters to several centimeters in diameter. BCC is a nonmelanocytic skin cancer (i.e., an epithelial tumor) that arises from basal cells, which are small round cells found in the lower layer of the epidermis. Basal cells invade the dermis, but seldom invade other parts of the body. Body distribution of BCCs is on the head (70%), trunk (25%) and penis, vulva or perianal skin (5%).
A 78-year-old female patient had been operated on 15 years ago for basal cell carcinoma. Recently, a disease relapse was diagnosed, and she underwent radiotherapy. After therapy, the patient was referred for an FDG PET/CT scan that detected a second disease relapse involving the left hemithorax (Fig. 14.1).
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Case 15 Clinical Diagnosis: Graves-Basedow Disease
a
b
⊡ Fig. 15.1 FDG PET/CT (a: MIP image) demonstrated increased tracer uptake (SUV max 5.8) involving the thyroid (b: CT scan; c: fused
32
c
images) consistent with a diffuse inflammation of the gland
Case 15 Clinical Diagnosis: Graves-Basedow Disease
1
⊡ Graves-Basedow Disease Clinical Case Graves’ disease is an inherited autoimmune disease in which the immune system attacks the thyroid gland, which then overproduces thyroid hormone. Graves-Basedow disease is a disorder characterized by a triad of hyperthyroidism, goiter and exophthalmos (bulging eyeballs). The etiology is unknown; it may be related to a malfunction of the immune system. Female dominance is seen at a 4:1 ratio; onset is commonly in the third to fifth decades of life. The severe form of exophthalmos occurs only in a minority of patients with the disorder, and it is also known as infiltrative ophthalmopathy, Graves’ ophthalmopathy or thyroid eye disease (TED). The symptoms include cardiac arrhythmias, increased pulse rate, weight loss in the presence of increased appetite, intolerance to heat, elevated basal metabolism rate, profuse sweating, apprehension, weakness, elevated proteinbound iodine level, tremor, diarrhea, headache, vomiting, eyelid retraction and staring. Extremely manifested disease that can sometimes be life threatening is called the thyroid storm (coma).
A 31-year-old female patient was affected by myasthenia. She was referred for an FDG PET/CT scan to exclude a thymoma. The scan was negative for thymoma but demonstrated the presence of increased tracer uptake in the thyroid (Fig. 15.1). Subsequent US, scintigraphy and hormonal dosage confirmed the presence of Graves-Basedow disease.
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Case 16 Clinical Diagnosis: Erysipelas
a
b
34
⊡ Fig. 16.1 FDG PET/CT (a: MIP image) demonstrated a diffusely increased tracer uptake (SUV max 9.1) (b: three planes fused images) in the left
lower limb, consistent with a knee prosthesis infection associated to subcutaneous infection
Case 16 Clinical Diagnosis: Erysipelas
1
⊡ Erysipelas Clinical Case Erysipelas is a superficial bacterial skin infection that characteristically extends into the cutaneous lymphatics. Bacterial inoculation into an area of skin trauma is the initial event in developing erysipelas. Thus, local factors, such as venous insufficiency, stasis ulcerations, inflammatory dermatoses, dermatophyte infections, insect bites and surgical incisions, have been implicated as portals of entry. In erysipelas, the infection rapidly invades and spreads through the lymphatic vessels. This can produce overlying skin “streaking” and regional lymph node swelling and tenderness. Pruritus, burning and tenderness are typical complaints. Streptococci are the primary cause of erysipelas. Most facial infections are attributed to group A streptococci, with an increasing percentage of lower extremity infections being caused by nongroup A streptococci.
An 81-year-old female patient had a history of rheumatoid arthritis, scleroderma and bilateral lower limb deep vein thrombosis. She was referred for an FDG PET/CT scan because of suspicion of knee prosthesis infection due to left lower limb pain, tenderness and fever. The scan highlighted signs of knee infection (Fig. 16.1) associated with a diffuse increased tracer uptake in the subcutaneous tissues of the left lower limb consistent with erysipelas.
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Case 17 Clinical Diagnosis: Initial Stage Discitis
a
b
c
36
⊡ Fig. 17.1 FDG PET/CT (a: MIP image) demonstrated increased tracer uptake (SUV max 5) involving L5 and S1 (white arrows on c), without any increased uptake in the corresponding
disk. This is consistent with an initial inflammatory process. Corresponding CT images (b) are still no
Case 17 Clinical Diagnosis: Initial Stage Discitis
1
⊡ Discitis Clinical Case Discitis, or disc space infection, is an inflammatory lesion of the intervertebral disc that occurs in adults, but more commonly in children. The infection probably begins in one of the contiguous end plates, and the disc is infected secondarily. As the disc space has no direct blood supply in adults, this space is secondarily involved when a hematogenous infection spreads to bone and subsequently spreads to the adjacent intervertebral disc space. However, infection can also spread from the disc space to adjacent bone when infection arises after surgery or following disc space injections. Pathogens can reach the bones of the spine by three basic routes: hematogenous spread from a distant site or focus of infection, direct inoculation from trauma or spinal surgery, and contiguous spread from adjacent soft tissue infection. Severe back pain that begins insidiously is characteristic of the disease. Mortality is rare, but morbidity is common; in addition, delays in diagnosis can lead to disabling complications due to vertebral collapse. An early diagnosis and appropriate treatment may prevent morbidity.
A 24-year-old male patient presented with persistent back pain unresponsive to medications. MRI demonstrated an altered but nonspecific signal in L5-S1. The patient was subsequently referred for an FDG PET/CT scan that turned out to be positive in L5-S1, with intersomatic disk sparing (Fig. 17.1). The patient underwent a vertebral biopsy, confirming bacterial infection.
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Case 18 Clinical Diagnosis: Erdheim-Chester Disease
a
⊡ Fig. 18.1 FDG PET/CT (a: CT scan; b: fused images) demonstrated increased tracer uptake (SUV max 13.6) involving the soft tissues and
38
b
bone of the left upper limb and right lower limb
Case 18 Clinical Diagnosis: Erdheim-Chester Disease
1
⊡ Erdheim-Chester Disease Clinical Case Erdheim-Chester disease is a rare disease characterized by the abnormal multiplication of a specific type of white blood cells called histiocytes or tissue macrophages. It is a non-Langerhans-cell histiocytosis. Usually, onset is in middle age. The disease involves an infiltration of lipid-laden macrophages, multinucleated giant cells, an inflammatory infiltrate of lymphocytes and histiocytes in the bone marrow, and a generalized sclerosis of the long bones. Long bone involvement is almost universal in ECD patients, and is bilateral and symmetrical in nature. More than 50% of cases have some sort of extraskeletal involvement. Current treatment options include surgical debulking, high-dose corticosteroid therapy, cyclosporine, interferon-a, chemotherapy and radiation therapy.
A 29-year-old male patient presented with the diagnosis of Erdheim-Chester disease, with right atrial localization. No specific symptoms were present in the clinical history. The patient was subsequently referred for an FDG PET/CT scan to exclude other sites of disease (Fig. 18.1). The scan identified increased tracer uptake in soft tissues and bone of the left upper limb and right lower limb, consistent with previously unknown sites of disease.
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Case 19 Clinical Diagnosis: Necrotizing Fasciitis
a
b
c
40
⊡ Fig. 19.1 FDG PET/CT (a: MIP image) showed a large area of increase (SUV max 13) in the soft tissues of the right pelvis (b: CT scan; c: fused
images), consistent with a severe inflammatory process
Case 19
Clinical Diagnosis: Necrotizing Fasciitis
1
⊡ Necrotizing Fasciitis Clinical Case Necrotizing fasciitis is a progressive, rapidly spreading, inflammatory infection located in the deep fascia, with secondary necrosis of the subcutaneous tissues. Because of the presence of gas-forming organisms, subcutaneous air is classically described in necrotizing fasciitis. This may be seen only on radiographs or not at all. The speed of spread is directly proportional to the thickness of the subcutaneous layer. Necrotizing fasciitis moves along the deep fascial plane. These infections can be difficult to recognize in their early stages, but they rapidly progress and require prompt recognition and aggressive treatment to combat the associated high morbidity and mortality. The causative bacteria may be aerobic, anaerobic or mixed flora, and the expected clinical course varies from patient to patient.
A 47-year-old female patient was treated with acupuncture for low back pain. A few days later, she progressively developed pain irradiating to the right lower limb and fever. The patient was subsequently referred for an FDG PET/CT scan to highlight occult foci of inflammation (Fig. 19.1). The scan demonstrated a large area of increased in the soft tissues of the right pelvis consistent with a severe inflammatory process that was subsequently proven to be necrotizing fasciitis.
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Case 20 Clinical Diagnosis: Vaquez Disease
a
b
42
⊡ Fig. 20.1 FDG PET/CT (a: MIP image) showed increased tracer uptake of diffuse bone marrow (b: CT, PET and fused images of the spine), consistent with a myeloproliferative disorder
Case 20
Clinical Diagnosis: Vaquez Disease
1
⊡ Vaquez Disease Clinical Case Vaquez disease is a chronic myeloproliferative disorder characterized by an increased red blood cell production. Excessive proliferation of the myeloid lineage is observed as well. The major symptoms are related to hypertension or to vascular abnormalities caused by the increased red cell mass. The cause is unknown. With currently available treatment, the median survival exceeds 10 years.
A 79-year-old male patient presented with itching, headaches and hypertension. He had an increased red blood cell count. The abdominal US demonstrated splenomegaly, and an FDG PET/CT scan (Fig. 20.1) was suggested to exclude a lymphoma. The scan demonstrated diffuse increased bone marrow uptake without significant increasing uptake in the spleen. After considering a proper diagnostic flow chart, the diagnosis was Vaquez disease (polycythemia rubra vera).
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Case 21 Clinical Diagnosis: Peritoneal Catheter Infection
a
b
⊡ Fig. 21.1 FDG PET/CT (a: MIP image) demonstrating an abdominal line of increased tracer (SUV max 4.1) corresponding the catheter
44
c
access (b: CT scan; c: fused images) consistent with an inflammatory process
Case 21
Clinical Diagnosis: Peritoneal Catheter Infection
1
⊡ Dialysis Catheter Infection Clinical Case Dialysis catheter infections are one of the most common complications of both hemodialysis and peritoneal dialysis. Catheter infections are typically caused by Staphylococcus aureus, commonly found bacteria on the surface of the skin. These infections may affect the catheter exit site, cuff or tunnel. Catheter infections are typically treated with a course of IV antibiotics and/or pills. If antibiotic therapy does not resolve the infection, the catheter may need to be removed.
A 55-year-old male patient was affected by chronic renal failure and was treated with peritoneal dialysis. He presented with a persistent mild fever without any evident cause. He was referred for an FDG PET/CT scan highlighting an area of increased uptake in the abdominal wall, corresponding to the dialysis catheter access (Fig. 21.1). This was consistent with catheter infection. The catheter was removed, and the infection was microbiologically proven.
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Case 22 Clinical Diagnosis: Implantable Cardiac Device Infection
⊡ Fig. 22.1 FDG PET/CT demonstrated three positive focal areas (arrrows on MIP) in the PM pocket and along the electrocatheter. SUV max was 1.8, consistent with initial infection
46
Case 22
Clinical Diagnosis: Implantable Cardiac Device Infection
1
⊡ Fig. 22.2 FDG PET/CT demonstrated an increase of the metabolic areas (arrows on MIP) in terms of extension and SUV (SUV max 8). The infection was in progression
⊡ Implantable Cardiac Device (ICD) Infection Bacterial infection of the ICD pocket is not an infrequent event. In this case, a prompt antibiotic therapy and PM explant is indicated to avoid septic dissemination in the blood flow. The infection and response to therapy can be difficult to diagnose, and FDG PET/CT may be of great value in equivocal cases.
Clinical Case A 52-year-old male pacemaker (PM) carrier presented with mild fever and mild alteration of serum inflammation markers. No clinical signs were present. The patient was referred for an FDG PET/CT (Fig. 22.1), and the results were positive for PM pocket infection. The patient underwent a 2-week antibiotic therapy and a subsequent second FDG PET/CT control (Fig. 22.2).
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Case 23 Clinical Diagnosis: Thoracic Aortic Graft Infection
a
b
c
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⊡ Fig. 23.1 FDG PET/CT (a: MIP image) showed an area of increased tracer (SUV max 9.6) in the posterior mediastinum corresponding to the
thoracic aorta wall (b: CT scan; c: fused images), consistent with an inflammatory process
Case 23 Clinical Diagnosis: Thoracic Aortic Graft Infection
1
⊡ Thoracic Aortic Graft Infection Clinical Case Infected aneurysms of the thoracic aorta are rare. S. aureus and Salmonella are the predominant pathogens. Presenting symptoms are often nonspecific. Because of insidious onset, the clinical presentation is often due to the complication of aneurysm rupture. Surgery remains the definitive treatment, but in the early years, the hospital mortality rate and the aneurysmrelated mortality rate were as high as 38% and 40% respectively in patients with infected suprarenal or thoracic aortic aneurysm.
A 57-year-old male patient presented with a large aneurysm of the descending thoracic aorta treated with a stent-graft endovascular implant. A few days later, he presented with fever of unknown origin that continued for months despite extensive diagnostic investigation and several cycles of empiric antibiotic therapy (Fig. 23.1). He was admitted to the hospital because of fever and worsening of his general condition, and was referred for an FDG PET/CT study, demonstrating an area of increased tracer in the posterior mediastinum corresponding to the thoracic aorta wall, consistent with an inflammatory process.
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Case 24 Clinical Diagnosis: Rheumatoid Arthritis
a
b
⊡ Fig. 24.1 FDG PET/CT (a: MIP image) showed several areas of increased tracer uptake (SUV max 9.6) involving the major joints (b: CT scan;
50
c
c: fused images), consistent with an inflammatory process. Left basal lung cancer was also evident (arrow)
Case 24 Clinical Diagnosis: Rheumatoid Arthritis
1
⊡ Rheumatoid Arthritis Clinical Case Rheumatoid arthritis (RA) is a chronic, systemic inflammatory disorder that can affect many tissues and organs, but principally attacks synovial joints. The process produces an inflammatory response of the synovium (synovitis) secondary to hyperplasia of synovial cells, excess synovial fluid and the development of pannus in the synovium. The pathology of the disease process often leads to the destruction of articular cartilage and ankylosis of the joints. Rheumatoid arthritis can also produce diffuse inflammation in the lungs, pericardium, pleura and sclera, and also nodular lesions, most commonly in subcutaneous tissue. Although the cause of rheumatoid arthritis is unknown, autoimmunity plays a pivotal role in both its chronicity and progression, and RA is considered a systemic autoimmune disease.
A 61-year-old female patient was affected by rheumatoid arthritis. During the routine controls, an unclear area of increased density emerged in the basal left lung. She was referred for an FDG PET/CT, which demonstrated increased tracer uptake in the lung, consistent with malignancy, and increased tracer uptake in all the major joints, consistent with rheumatoid arthritis (Fig. 24.1).
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Case 25 Clinical Diagnosis: Idiopathic Mediastinal Fibrosis
a
b
c
52
⊡ Fig. 25.1 FDG PET/CT (a: MIP image) showed an area of increased tracer (SUV max 4.2) in the anterior mediastinum close to the aortic arch
(b: CT scan; c: fused images), consistent with an active inflammatory process
Case 25
Clinical Diagnosis: Idiopathic Mediastinal Fibrosis
1
⊡ Idiopathic Mediastinal Fibrosis Clinical Case Idiopathic mediastinal fibrosis is also known as chronic fibrosis or fibrosing mediastinitis or chronic mediastinal fibrosis, or cryptogenic mediastinal fibrosis, all terms suggestive of slowly progressive envelopment of mediastinal structures in proliferating fibrous scar tissue. Mediastinal structures are surrounded, constricted and sometimes invaded by the fibrous tissue, which may extend to affect other intrathoracic organs. The pattern of involvement of the mediastinum is variable and so are the clinical features. Venous structures, due to thin walls and low intraluminal pressure, tend to be compressed earlier than the arteries and tracheobronchial tree and esophagus. For this reason venous hypertension in the drainage area of the superior vena cava is considered the hallmark of the disease. It is a rare cause of superior vena cava obstruction (1–2%). Medical therapy is discouraging, and surgery has limitations, while stenting of vessels and dilatation of the bronchi and esophagus may provide some relief to patients.
A 42-year-old female patient presented with chest pain and left shoulder pain. A chest X-ray revealed a mass in the left superoanterior mediastinum. Contrastenhanced chest computed tomography (CT) demonstrated noncalcified softtissue infiltration beginning at the neck and encasing the mediastinal structure. Since malignancy could not be excluded, she was referred for an FDG PET/CT scan demonstrating a mild uptake in the anterior mediastinum (Fig. 25.1). She subsequently underwent a biopsy that was positive for mediastinal fibrosis, and immunosuppressive drugs were administrated. A second PET scan showed negative results.
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Case 26 Clinical Diagnosis: Spinal Disc Herniation
a
b
⊡ Fig. 26.1 FDG P ET/CT (a : MIP image) showed an area of mild increased tracer (white arrow, SUV max 2.4) in the spinal cord ( b: CT scan; c: 54
c
fused images) level T11-T12, consistent with disc herniation
Case 26 Clinical Diagnosis: Spinal Disc Herniation
1
⊡ Spinal Disc Herniation Clinical Case As a disc degenerates, it can herniate, which is known as a disc herniation or a herniated disc. The weak spot in the outer core of the disc is directly under the spinal nerve root, so a herniation in this area puts direct pressure on the nerve, which in turn can cause sciatica. Pain that radiates down the leg and is caused by a herniated disc is called a radiculopathy. Approximately 90% of disc herniations will occur toward the bottom of the spine at L4-L5 or L5-S1, which causes pain in the L5 nerve or S1 nerve, respectively.
A 35-year-old female patient was referred for an FDG PET/CT scan after the completion of therapy for follicular lymphoma (Fig. 26.1). At the moment of the scan, she presented with severe back pain. The PET was negative for lymphoma, but detected an area of mild increased tracer uptake in the spinal cord. She subsequently underwent an MR, which indicated the presence of a spinal herniated disc.
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Case 27 Clinical Diagnosis: Mesenteritis
a
b
56
⊡ Fig. 27.1 FDG PET/CT (a: MIP image) showed an area of increased tracer uptake (SUV max 7.3) involving the mesentery (b: CT scan;
c
c: fused images), consistent with an active inflammatory process
Case 27 Clinical Diagnosis: Mesenteritis
1
⊡ Mesenteritis Clinical Case Sclerosing mesenteritis is part of a spectrum (including mesenteric lipodystrophy and mesenteric panniculitis) of idiopathic primary inflammatory and fibrotic processes that affect the mesentery. Pathophysiologically, these processes may affect the integrity of the gastrointestinal lumen and mesenteric vessels by a mass effect. These are uncommon disorders that predominantly affect men between the fifth and seventh decades of life, and may result in a variety of gastrointestinal and systemic manifestations, including abdominal pain, nausea and vomiting, diarrhea, weight loss and fever. The etiology of sclerosing mesenteritis remains obscure, although several mechanisms have been suggested based upon anecdotal reports, small case series or extrapolation from animal models of inflammation. These include previous abdominal surgery or trauma, autoimmunity, paraneoplastic syndrome, ischemic injury and infection. Surgical biopsy is usually required to make the diagnosis and to exclude clinical and radiological mimics such as lymphoma, carcinoid syndrome and peritoneal carcinomatosis.
A 59-year-old male patient presented with nonspecific symptoms including fever, weight loss and abdominal pain. The CT showed a soft tissue mass in the small bowel mesentery. The patient was referred for an FDG PET/CT scan, which showed increased abdominal uptake (Fig. 27.1). The biopsy highlighted the presence of mesenteritis.
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Case 28 Clinical Diagnosis: Osteomyelitis of the Foot
a
b
c
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⊡ Fig. 28.1 FDG PET/CT (a: MIP image) showed a focal area of increased tracer uptake (SUV max 4.3) in the first toe of the right foot (b: CT scan;
c: fused images), consistent with an active bony inflammatory process
Case 28 Clinical Diagnosis: Osteomyelitis of the Foot
1
⊡ Osteomyelitis of the Foot Clinical Case Osteomyelitis of the foot is a bone infection that will cause bone destruction. It can occur anywhere in the body, but it is especially prevalent in the foot. The condition is caused when bacteria, in most cases, Staphylococcus aureus, invades a bone. Symptoms associated with osteomyelitis include local signs of pain, swelling and redness in the area of the infection. Systemic signs will include chills, fever and malaise. Early detection of osteomyelitis is very important in order to limit the destruction of bone and to have a better chance of resolving the infection with antibiotics. This is a disease that can be difficult to detect, and there are other conditions that may give falsepositive results to osteomyelitis tests. X-ray results are often initially inconclusive. Bone has to lose upwards of 50% of its density before changes will be seen on X-rays. By the time the bone has lost enough density to show up on X-rays (2–6 weeks), the bacteria have infiltrated the bone fairly well.
A 46-year-old male patient presented with fever and pain in the right foot that arose after a trauma. The bone scan was positive, but the white blood cell scintigraphy was negative. The biopsy was positive for infection. An FDG PET/CT scan was performed to assess the presence of bone involvement (Fig. 28.1).
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Case 29 Clinical Diagnosis: Peritoneal Mesothelioma
a
b
⊡ Fig. 29.1 FDG PET/CT (a: MIP image) showed 60
a focal area of increased tracer uptake (white arrow on a,b,c, SUV max 5) corresponding to
c
peritoneal thickening at CT (white arrow on b) (b: CT scan; c: fused images), consistent with malignancy
Case 29 Clinical Diagnosis: Peritoneal Mesothelioma
1
⊡ Peritoneal Mesothelioma Clinical Case Mesothelioma can arise both from visceral and parietal peritoneum. It is diagnosed in advanced stages in most cases, and it often takes considerable time to arrive at the correct diagnosis. The most frequently reported initial symptoms are abdominal pain (35%), abdominal swelling (31%), anorexia, marked weight loss and ascites; less frequently, night sweats and hypercoagulability occur. Clinical presentations with fever of unknown origin, intestinal obstruction or surgical emergency (due to acute inflammatory lesions) have been reported. Computed tomography (CT) findings of peritoneal mesothelioma are nonspecific and not sufficient to establish a diagnosis. The definitive diagnosis of peritoneal mesothelioma depends on histological and immunohistochemical examination. For patients with confirmed MPM, radical resection is associated with better prognoses and should be pursued when possible. Other treatments for peritoneal mesothelioma include intensive locoregional therapeutic strategies: cytoreductive surgery, hyperthermic intraoperative or early postoperative intraperitoneal chemotherapy and immunotherapy.
A 55-year-old male patient presented with ascites and anorexia. The CT scan showed an area of peritoneal thickening. An FDG PET/CT scan was performed (Fig. 29.1) to assess the presence of a malignancy. A subsequent biopsy diagnosed malignant peritoneal mesothelioma.
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Case 30 Clinical Diagnosis: Lymphoma of the Brain
a
b
c
62
⊡ Fig. 30.1 FDG PET/CT (a: MIP image) showed a large area of increased tracer uptake (SUV max 35) in the right hemisphere corresponding
to a clear solid mass at CT (b: CT scan; c: fused images), consistent with lymphoma. No other localizations were found
Case 30 Clinical Diagnosis: Lymphoma of the Brain
1
⊡ Lymphoma of the Brain Clinical Case Primary cerebral lymphomas are rare. They represent less than 1% of all CNS tumors. They can occur at any age, but are more common in the elderly. They affect males and females equally. Geographically, the disease is found worldwide. This type of tumor spreads by infiltration of the cerebrospinal fluid and seeding within the central nervous system. In less than 10% of patients, distant metastases occur in sites such as the viscera, bones and soft tissues. Primary cerebral lymphoma may be cured by radiotherapy and chemotherapy. Unfortunately, many of these tumors are incurable, and relapse occurs between 6 months and 2 years following initial treatment. Relapsed or recurrent disease generally has a very poor prognosis, often with death within a few months.
A 54-year-old male patient was referred for FDG PET/CT because of the diagnosis of lymphoma of the brain to exclude distant localizations of the disease (Fig. 30.1).
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Case 31 Clinical Diagnosis: Pilonidal Cyst
a
b
c
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⊡ Fig. 31.1 FDG PET/CT (a: MIP image lateral view) showed an area of FDG uptake in the soft tissues close to the coccyx (SUV max 8.5)
(b: CT scan; c: fused images), consistent with pilonidal cyst
Case 31 Clinical Diagnosis: Pilonidal Cyst
1
⊡ Pilonidal Cyst Clinical Case A pilonidal cyst is a cyst or abscess near or on the natal cleft of the buttocks that often contains hair and skin debris. Pilonidal cysts are often very painful, affect men more frequently than women, and typically occur between the ages of 15 and 24. Although usually found near the coccyx, the condition can also affect the navel, armpit or penis, though these locations are much more rare.
A 25-year-old male patient was referred for an FDG PET/CT scan (Fig. 31.1) for severe pain in the sacral region and a lytic area in the right sacrum at CT images. An area of FDG uptake was detected in the soft tissues, consistent with active inflammation. This was diagnosed as a pilonidal cyst. No abnormal FDG distribution was found in the sacrum.
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Cases 32–33 Clinical Diagnosis: Osteomyelitis of the Sternum
a
b
c
66
⊡ Fig. 32.1 FDG PET/CT (a : MIP image) showed a large area of increased tracer uptake (black arrow on a, white arrow on b and c, SUV max
7.9) involving the sternum and the retrosternal soft tissues (b : CT scan; c : fused images), consistent with infection
Cases 32–33 Clinical Diagnosis: Osteomyelitis of the Sternum
1
⊡ Osteomyelitis of the Sternum Clinical Case 32 Deep sternal wound infection after sternotomy for cardiac surgery is a serious complication that affects between 1% and 2.8% of patients, with an overall mortality rate between 25% and 52%. The infection always involves the sternum itself. Patients carrying a high risk for mediastinitis usually have an osteoporotic, fragile and broken sternum. During debridement, all foreign bodies as well as infected and necrotic tissue must be removed, which gives rise to a dead space in the sternal bone. Sternal osteomyelitis often persists after debridement for mediastinitis. Moreover, efforts to treat deep sternal wound infection sometimes meet with only partial success and result in localized sternal osteomyelitis. The persistently discharging sternal wound may not have systemic consequences, but it does affect the patient’s self-image and physical well-being.
A 63-year-old male patient was operated on for aortocoronary bypass. Three weeks later, he presented with persistent fever. He was referred for FDG PET/CT for fever of unknown origin, which showed increased tracer uptake in the sternum (Fig. 32.1). This was subsequently proved to be a bone infection.
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Cases 32–33 Clinical Diagnosis: Osteomyelitis of the Sternum
a
b
⊡ Fig. 33.1 FDG PET/CT (a: MIP image) showed a large area of increased tracer uptake (black arrow on a, white arrow on c, SUV max 18) 68
c
involving the left sternoclavicular joint (white arrow on c) (b: CT scan; c: fused images), consistent with infection
Cases 32–33 Clinical Diagnosis: Osteomyelitis of the Sternum
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Clinical Case 33 A 69-year-old female patient was operated on for laryngectomy for cancer. Ten days later she presented with persistent fever. She was referred for FDG PET/CT for fever of unknown origin, which demonstrated increased tracer uptake in the sternum (Fig. 33.1). This was subsequently proved to be a bone infection.
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Cases 34–35 Clinical Diagnosis: Paget’s Disease
a
b
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⊡ Fig. 34.1 FDG PET/CT (a: MIP image) showed a large area of diffuse and increased uptake involving the bony pelvis (black arrow on a, white arrow
c
on c, SUV max 21) corresponding to increased density at CT (white arrow on b) (b: CT scan; c: fused images), consistent with Paget’s disease
Cases 34–35 Clinical Diagnosis: Paget’s Disease
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⊡ Paget’s Disease Clinical Case 34 Paget’s disease is a disorder that affects the normal remodeling process of bone. In the remodeling process, old bone is removed and new bone is formed. In patients with Paget’s disease, this process is altered. These patients have an excessive amount of bone removal followed by an even more excessive amount of new bone formation. Unfortunately, this increased rate of bone remodeling leads to new bone that is weaker, has more blood vessels, and is larger in size than normal bone. While most cases do not cause symptoms, some patients may develop pain, fractures or even malignant transformation into sarcoma (bone tumor), although this is rare. Men are affected by Paget’s disease slightly more often than women (3:2 ratio). Paget’s disease is more common in patients of Northern European ancestry, most commonly found in those from Great Britain. It is rare in the Asian and African populations. It is more common with increasing age, being typically diagnosed in people in their fifties.
A 74-year-old male patient presented with dedifferentiated prostate cancer that was treated radically. An FDG PET/CT scan was performed (Fig. 34.1) to exclude bony metastasis due to bone pain and demonstrated increased tracer uptake in the bony pelvis. A subsequent biopsy diagnosed Paget’s disease.
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Cases 34–35 Clinical Diagnosis: Paget’s Disease
a
b
c
⊡ Fig. 35.1 FDG PET/CT (a: MIP image) showed 72
an area of increased uptake involving the sternum (white arrow on c, SUV max 5) correspond-
ing to increased density at CT (white arrow on b) (b: CT scan; c: fused images), consistent with Paget’s disease
Cases 34–35 Clinical Diagnosis: Paget’s Disease
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Clinical Case 35 A 32-year-old female patient was referred for an FDG PET/CT because of persistent chest pain and negative X-ray results (Fig. 35.1), demonstrating an area of increased uptake in the sternum. This proved to be Paget’s disease.
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Cases 36–38 Clinical Diagnosis: Postsurgical Bone Infection
a
b
c
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⊡ Fig. 36.1 FDG PET/CT (a: MIP image) showed an area of increased uptake in the proximal and distal part of the synthesis mean (white arrows
on c and black arrows a and b, SUV max 6.1) (b: CT scan; c: fused images), consistent with infection
Cases 36–38 Clinical Diagnosis: Postsurgical Bone Infection
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⊡ Postsurgical Bone Infection Clinical Case 36 In orthopedics, surgical site infection after implant surgery is a disaster both for the patient and surgeon. This may lead to increased antibiotic use, prolonged hospital stay, repeated debridements, prolonged rehabilitation, morbidity and mortality. The pathogenesis of infection in fractures fixation devices is related to microorganisms, which grow in biofilm, and therefore its eradication is difficult. These infections are classified into three stages, i.e., early (less than 2 weeks), delayed (2–10 weeks) and late (more than 10 weeks) infection. With proper aseptic measures, the infection rate has been reduced to 0.2% in recent times. The most common infecting organism in orthopedic infection is Staphylococcus aureus. The diagnosis of deep implant infection can be made by clinical examination, laboratory investigation, histopathology, microbiology and imaging studies, i.e., ultrasonography, threephase technetium-99, indium-111 and gallium-67 bone scan, magnetic resonance imaging (MRI) and computerized axial tomography (CT). Positron emission tomography or PET-CT is a new imaging diagnostic tool for implant-related deep infection. Biopsy can also be carried out for undiagnosed infections, but this is rarely done.
A 41-year-old male patient presented with persistent fever. He had previously been operated on for a multiple fractures of the right femur. An FDG PET/CT scan was performed (Fig. 36.1), demonstrating increased tracer uptake consistent with postsurgical infection.
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Cases 36–38 Clinical Diagnosis: Postsurgical Bone Infection
a
c
b
⊡ Fig. 37.1 FDG PET/CT (a: MIP image) showed 76
an area of increased uptake (black arrow on a, white arrow on c, SUV max 18) in the synthesis
Clinical Case 37 A 69-year-old female patient was referred for an FDG PET/CT because of persistent fever (Fig. 37.1) after an intervention for spine stabilization due to discitis. The scan demonstrated increased tracer uptake corresponding to the synthesis mean, consistent with infection.
mean (white arrow on b) (b: CT scan; c: fused images), consistent with infection
Cases 36–38 Clinical Diagnosis: Postsurgical Bone Infection
1
a
c
b
⊡ Fig. 38.1 FDG PET/CT (a: MIP image) showed an area of increased uptake in the right acetabulum (black arrow on a, white arrow on b
and c, SUV max 7.3) (b: CT scan; c: fused images), consistent with peri-prosthetic infection
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Clinical Case 38 A 79-year-old female patient was operated on for right hip prosthesis. She was referred for an FDG PET/CT because of persistent fever (Fig. 38.1) and pain in the right hip. The scan demonstrated increased tracer uptake in the right acetabulum, consistent with infection.
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Cases 39–40 Clinical Diagnosis: Pigmented Villonodular Synovitis
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b
c
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⊡ Fig. 39.1 FDG PET/CT (a: MIP image) showed an area of increased uptake in the cartilage of the right knee (SUV max 5.8) (b: CT scan; c: fused
images), consistent with persistent active inflammation
Cases 39–40 Clinical Diagnosis: Pigmented Villonodular Synovitis
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⊡ Pigmented Villonodular Synovitis Clinical Case 39 Pigmented villonodular synovitis (PVNS) is a rare proliferative process that affects the synovium in young and middle-aged adults. The estimated annual incidence is 1.8 patients per million. The sex distribution is variable. PVNS is usually monoarticular and often arises in the joints, although it may be found in a tendon or bursa. PVNS may present as a localized nodule, usually arising in the hand, or as a diffuse process, usually found in the knee. Localized PVNS is sometimes referred to as giant cell tumor of the tendon sheath, particularly when it occurs in the hand. PVNS may be locally destructive and involve muscles, tendons, bone and skin. The etiology of PVNS is unclear. It has been postulated that PVNS may develop because of an inflammatory process or a disturbance of the lipid metabolism. The majority of investigators seem to favor a chronic inflammatory process. Patients frequently present with pain, joint effusions and swelling. The duration of symptoms is variable.
A 49-year-old female patient was affected by pigmented villonodular synovitis. She was referred for an FDG PET/CT scan (Fig. 39.1) during antiinflammatory therapy to assess its effect. An area of persistent FDG uptake was detected in the right knee cartilage, consistent with active inflammation.
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Cases 39–40 Clinical Diagnosis: Pigmented Villonodular Synovitis
a
b
⊡ Fig. 40.1 FDG PET/CT (a: MIP image) showed an area of increased uptake in the cartilage of the right knee (SUV max 9.3) (b: CT scan; c: fused 80
c
images), consistent with persistent active inflammation
Cases 39–40 Clinical Diagnosis: Pigmented Villonodular Synovitis
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Clinical Case 40 A 69-year-old female patient was affected by pigmented villonodular synovitis. She was referred for an FDG PET/CT scan (Fig. 40.1) during antiinflammatory therapy to assess its effect. An area of persistent FDG uptake was detected in the right knee cartilage, consistent with active inflammation.
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Case 41 Clinical Diagnosis: Vascular Graft Infection
a
b
c
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⊡ Fig. 41.1 FDG PET/CT (a: MIP image) showed an area of FDG uptake (black arrow on a, white arrow on c) in the left graft (white arrow on b)
consistent with active inflammation (SUV max 6.5) (b: CT scan; c: fused images)
Case 41
Clinical Diagnosis: Vascular Graft Infection
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⊡ Vascular Graft Infection Clinical Case Surgical wounds can be classified according to the likelihood of bacterial contamination and, consequently, of wound infection (WI). A clean wound implies a lack of infection within the surgical field, no entry into the respiratory, urogenital or gastrointestinal tracts, and absence of external contamination; in these circumstances, the risk of WI is very low. Surgery on the arterial tree of the lower limbs is an exception, with a significantly higher incidence of WI than the average clean wound, so much so that routine antibiotic prophylaxis is indicated even when prosthetic material is not used. Among patients undergoing lower limb arterial surgery, increased WI risk has been linked with several factors such as sex, diabetes, presence of tissue loss, previous surgery, surgery on the lower extremities, use of vein grafts and groin incision, with little agreement among published studies.
A 55-year-old male patient was operated on for an aorto-bisiliac graft and then referred for an FDG PET/CT scan (Fig. 41.1) for suspect infection. An area of FDG uptake was detected in the left graft, consistent with active inflammation.
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Case 42 Clinical Diagnosis: Atrial Sarcoma
a
b
c
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⊡ Fig. 42.1 FDG PET/CT (a: MIP image) showed an area of FDG uptake in the left atrium consistent with malignancy (SUV max 8) (b: contrast-enhanced CT scan; c: fused images)
Case 42 Clinical Diagnosis: Atrial Sarcoma
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⊡ Atrial Sarcoma Clinical Case Primary cardiac sarcoma is a rare malignant neoplasm, with an incidence of 0.0001% in collected autopsy series. Angiosarcoma is the most common cardiac sarcoma and is present in up to 33% of the cases that are associated with a poor prognosis. Because angiosarcoma is essentially not responsive to current regimens of chemotherapy and irradiation, early complete resection is recommended as the treatment choice. However, complete resection is difficult because of the limited amount of myocardium and expansion of the tumor at the time of diagnosis.
A 39-year-old male patient was referred for an FDG PET/CT scan (Fig. 42.1) for staging atrial sarcoma. An area of FDG uptake was detected in the left atrium, consistent with malignancy. No other sites of active disease were detected.
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Case 43 Clinical Diagnosis: Avascular Necrosis of Bones
a
b
⊡ Fig. 43.1 FDG PET/CT (a: MIP image) showed an area of FDG uptake in the left distal femoral diaphysis and left proximal tibial epiphysis 86
c
(black arrows on a, white arrow on b and c, SUV max 5.9) (b: CT scan; c: fused images), consistent with necrosis
Case 43 Clinical Diagnosis: Avascular Necrosis of Bones
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⊡ Avascular Necrosis of Bones Clinical Case Avascular necrosis is a disease where there is cellular death of bone components due to interruption of the blood supply. Without blood, the bone tissue dies, and the bone collapses. If avascular necrosis involves the bones of a joint, it often leads to destruction of the joint articular surfaces. There are many theories about what causes avascular necrosis. Proposed risk factors include chemotherapy, alcoholism, excessive steroid use, post trauma, caisson disease, vascular compression, hypertension, vasculitis, arterial embolism and thrombosis, damage from radiation, bisphosphonates (particularly the mandible), sickle cell anemia, Gaucher’s disease and deep diving. In some cases it is idiopathic (no cause is found). Rheumatoid arthritis and lupus are also common causes of AVN.
A 13-year-old male patient was treated with corticosteroids for autoimmune piastrinopenia. He presented with acute pain in the left knee and was referred for an FDG PET/CT (Fig. 43.1) to exclude osteomyelitis, suspected at MR. The scan showed increased uptake in the left distal femoral diaphysis and left proximal tibial epiphysis. This was subsequently diagnosed as avascular necrosis due to corticosteroids.
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Case 44 Clinical Diagnosis: Malignant Otitis
a
b
c
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⊡ Fig. 44.1 FDG PET/CT (a: MIP image) showed an area of FDG uptake in the right ear (black arrow on a, white arrows on c, SUV max 19), also
involving the adjacent bone (white arrows on b) (b: CT scan; c: fused images), consistent with inflammation
Case 44 Clinical Diagnosis: Malignant Otitis
1
⊡ Malignant Otitis Clinical Case Malignant otitis externa is a disorder involving inflammation and damage of the bones and cartilage at the base of the skull. It is caused by the spread of an outer ear infection (otitis externa, also called swimmer’s ear). It is an uncommon complication of both acute swimmer’s ear and chronic swimmer’s ear. Risks for this condition include chemotherapy, diabetes and a weakened immune system. External otitis is often caused by difficult-totreat bacteria such as pseudomonas. The infection spreads from the floor of the ear canal to the nearby tissues and into the bones at the base of the skull. The infection and inflammation may damage or destroy the bones. The infection may spread more and affect the cranial nerves, brain or other parts of the body.
A 63-year-old male patient was affected by malignant otitis and therefore referred for an FDG PET/CT (Fig. 44.1) to evaluate the extension of the inflammatory area. The scan showed increased uptake in the right ear, also involving the adjacent bone.
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Case 45 Clinical Diagnosis: Bone Sarcoidosis
a
b
c
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⊡ Fig. 45.1 FDG PET/CT (a: MIP image) showed increased FDG uptake in multiple lymph nodes of the mediastinum and bilateral axilla (SUV
max 11) and in bones (lumbar vertebrae, bony pelvis) (b: CT scan; c: fused images), consistent with sarcoidosis
Case 45 Clinical Diagnosis: Bone Sarcoidosis
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⊡ Bone Sarcoidosis Clinical Case The frequency of bone involvement varies from 3% to 13%. Sarcoidosis bone lesions are characterized by their bilateral distribution, the site of origin (cortical, preservation of the periosteum), location (hands and feet), position (usually the ends of the affected bones) and shape (cystic or lacelike with minimal disturbance in the nearby soft tissues). In sarcoid bone lesions the cortical borders of the bones are well preserved. Articular disease is usually manifested by soft tissue swelling and effusions. In advanced cases, as subchondral lesions extend into joint spaces, the adjacent joints may be involved. Calcification is absent. The questions regarding the causation and localization of bone lesions in sarcoidosis remain unanswered. Since the lesions occur mostly in non-weight-bearing bones (hands), they show features of increased bone resorption rather than bone production. Insufficient osteogenesis in relation to osteolysis results in the decrease of total bone mass and hence in the decrease of bone density. Osteoporosis is evident radiologically because of thin cortices and sharp, widely spaced, often palisading trabeculae.
A 29-year-old male patient was affected by sarcoidosis and therefore referred for an FDG PET/CT (Fig. 45.1) to evaluate the disease activity. Previously unknown bone localizations were present.
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Case 46 Clinical Diagnosis: Polydermatomyositis
a
b
⊡ Fig. 46.1 FDG PET/CT (a: MIP image) showed increased FDG uptake in the skin, especially in lower limbs, corresponding to calcifications at CT
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c
(SUV max 3.2) (b: CT scan; c: fused images), consistent with active inflammation (arrows on a,b,c)
Case 46 Clinical Diagnosis: Polydermatomyositis
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⊡ Polydermatomyositis Clinical Case Idiopathic inflammatory myopathies are a heterogeneous group of autoimmune disorders predominantly affecting skeletal muscles, resulting in muscle inflammation and weakness. Along with the musculoskeletal manifestations, involvement of other organ systems is seen, including the skin, cardiac, gastrointestinal, and pulmonary systems. The three most common inflammatory myopathies are polymyositis (PM), dermatomyositis (DM) and inclusion body myositis (IBM). The classic clinical finding of polydermatomyositis is the progressive development of symmetric proximal muscle and truncal weakness that develops relatively slowly over the course of weeks to months. Facial muscles remain unaffected; however, pharyngeal and respiratory muscles can be affected. The joints, skin, cardiac and pulmonary systems, and the gastrointestinal tract are affected. Extramuscular organ involvement, such as interstitial lung disease and cardiac involvement, is associated with worse prognosis. Joint involvement can occur and is characterized by arthralgias and arthritis. It is usually noted early in the course of disease, involving wrists, knees and the small joints of the hands. Joint involvement is classically nonerosive and frequently responsive to the treatment of the underlying inflammatory myopathy. Dermatologic, gastrointestinal, cardiac and pulmonary manifestations can be associated as well.
A 55-year-old female patient was affected by polydermatomyositis and referred for an FDG PET/CT (Fig. 46.1) to evaluate the activity of the disease during anti-inflammatory therapy. The scan was positive for multiple localizations in the skin, still active despite therapy.
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Case 47 Clinical Diagnosis: RS3PE
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b
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⊡ Fig. 47.1 FDG PET/CT (a: MIP image) showed increased FDG uptake in the mediastinal lymph nodes and distal esophagus (SUV max 8) (b: fused images), consistent with active inflammation
Case 47 Clinical Diagnosis: RS3PE
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⊡ RS3PE Clinical Case Remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome is a definite subset of the seronegative symmetrical polyarthritis of the aged, characterized by dramatic pitting edema of the hands, male predominance, old age and exquisite response to corticosteroids. RS3PE syndrome is a rare but well-defined syndrome known to be associated with solid tumors and hematological malignancies. Recent research has shown that it is not a specific entity, but rather a syndrome that can represent the inaugural form of various types of rheumatic disease and neoplastic conditions of the elderly. A thorough examination in elderly patients with RS3PE syndrome and heightened suspicion of potential underlying malignant disease are necessary. In 1985, McCarty et al. first described Remitting Seronegative Symmetrical Synovitis with Pitting Edema (RS3PE) syndrome, which is characterized by symmetrical distal synovitis, tenosynovitis of the mucous sheaths of the flexor and extensor tendons of the hands, pitting edema of the hands and/or feet, seronegativity for the rheumatoid factor (RF) and benign prognosis, mainly affecting the elderly and the males, exquisite response to corticosteroids and long-term remission after withdrawal. Although the RS3PE syndrome appeared as a well-characterized entity, recent research has shown that it is not a specific entity, but rather a syndrome that can represent the inaugural form of various types of rheumatic disease and neoplastic conditions of the elderly.
A 51-year-old female patient was referred for an FDG PET/CT scan (Fig. 47.1) to exclude the presence of malignancies after the diagnosis of RS3PE. The scan demonstrated increased FDG uptake in the mediastinal lymph nodes and distal esophagus; this was subsequently proved to be related, respectively, with sarcoidosis and Barret’s esophagus.
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Cases 48–49 Clinical Diagnosis: Tuberculosis
⊡ Fig. 48.1 FDG PET/CT (MIP image) showed increased FDG uptake in the bowel (SUV max 25), consistent with active inflammation
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Cases 48–49 Clinical Diagnosis: Tuberculosis
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⊡ Tuberculosis Clinical Case 48 Tuberculosis (TB), a multisystemic disease with myriad presentations and manifestations, is the most common cause of infectious diseaserelated mortality worldwide. Although TB rates are decreasing in the United States, the disease is becoming more common in many parts of the world. In addition, the prevalence of drug-resistant TB is also increasing worldwide. Co-infection with the human immunodeficiency virus (HIV) has been an important factor in the emergence and spread of resistance. Mycobacterium tuberculosis, a tubercle bacillus, is the causative agent of TB. It belongs to a group of closely related organisms—including M. africanum, M. bovis and M. microti —in the M. tuberculosis complex. Although the lung is the most commonly involved organ, many other localizations of the bacterium may be present. In particular extrapulmonary manifestations may occur in the skin, eye, bones, soft tissues and central nervous system.
A 13-year-old female patient was diagnosed with abdominal tuberculosis and was referred for an FDG PET/CT scan to assess the disease extension and activity before therapy (Fig. 48.1). The scan showed diffuse intestinal FDG uptake and increased uptake in the mediastinal lymph nodes.
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Cases 48–49 Clinical Diagnosis: Tuberculosis
a
b
c
d
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⊡ Fig. 49.1 FDG PET/CT (a: MIP image) showed increased FDG uptake in the proximal right femur and soft tissues (SUV max 15) (b: fused images), consistent with active inflammation.
During therapy (c: MIP image, d: fused images) the SUV max significantly decreased (SUV max 3), indicating a good response to therapy
Cases 48–49 Clinical Diagnosis: Tuberculosis
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Clinical Case 49 A 41-year-old male patient was affected by a tubercular abscess. He was referred for an FDG PET/CT scan to assess the disease extension and activity before therapy. The scan showed increased FDG uptake in the proximal right femur and soft tissues, consistent with active inflammation (Fig. 49.1). During therapy a second scan was performed and demonstrated a very good response to therapy.
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Case 50 Clinical Diagnosis: Sacroiliitis
a
b
c
⊡ Fig. 50.1 FDG PET/CT (a: MIP image) showed increased FDG uptake in the right sacroiliac joint (black arrow on c, SUV max 5) (b: CT scan; c: fused images), consistent with active inflammation
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Case 50 Clinical Diagnosis: Sacroiliitis
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⊡ Sacroiliitis Clinical Case Sacroiliitis is an inflammation of one or both of the sacroiliac joints. Sacroiliitis can cause pain in the lower back, and may even extend to one or both legs. The pain associated with sacroiliitis is often aggravated by prolonged standing or by stair climbing. Sacroiliitis has been linked to a group of diseases called spondyloarthropathies, which cause inflammatory arthritis of the spine. Sacroiliitis can be difficult to diagnose, because it may be mistaken for other causes of low back pain. Treatment of sacroiliitis may involve a combination of rest, physical therapy and medications.
A 56-year-old female patient was in followed up for breast cancer. Due to bone pain, she was referred for an FDG PET/CT (Fig. 50.1) detecting diffuse FDG uptake in the right sacroiliac joint. This was consistent with sacroiliitis. The patient was treated with antiinflammatory drugs, and the pain progressively disappeared.
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Case 51 Clinical Diagnosis: Pulmonary MALT Lymphoma
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b
c
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⊡ Fig. 51.1 FDG PET/CT (a: MIP image) showed increased FDG uptake in the left lung (black arrow on a, white arrow on b and c, SUV max 7)
(b: CT scan; c: fused images) consistent with MALT. Increased uptake in the esophagus was consistent with active diffuse inflammation
Case 51 Clinical Diagnosis: Pulmonary MALT Lymphoma
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⊡ MALT Lymphoma Clinical Case This entity represents about 8% of all nonHodgkin’s lymphomas and was recently re-classified as “extranodal marginal zone lymphomas of MALT type.” The term marginal zone lymphoma (MZL) encompasses the three closely related lymphoma subtypes of nodal, primary splenic and extranodal lymphomas of MALT type: the latter represent the vast majority of MZL. These lymphomas arise at different anatomic sites, are composed of mature B-cells lacking expression of CD5 and CD10, and often present with overlapping morphologic features, but typically quite distinct clinical behaviors. Only very recently cytogenetic/molecular genetic observations have underlined the distinctiveness of these three lymphoid neoplasms, which in both the R.E.A.L. and WHO classifications are included under the general term of MZL. MALT lymphomas arise in numerous extranodal sites, but gastric MALT lymphoma is the most common and best studied, and is, therefore, the paradigm for the group as a whole.
A 73-year-old male patient was diagnosed with a left pulmonary mass at CT. The mass was biopsied, and the final diagnosis was pulmonary MALT lymphoma (extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue). The patient was referred for an FDG PET/CT (Fig. 51.1) to stage the disease. The scan showed FDG uptake in the left pulmonary lesion, without any other evidence of disease.
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Case 52 Clinical Diagnosis: Fibrosarcoma
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b
c
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⊡ Fig. 52.1 FDG PET/CT (a: MIP image) showed focal increased FDG uptake in the cervical lesion (black arrow on a, white arrow on b anc c, SUV
max 11) (b: CT scan; c: fused images), consistent with fibrosarcoma
Case 52 Clinical Diagnosis: Fibrosarcoma
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⊡ Fibrosarcoma Clinical Case Fibrosarcoma (fibroblastic sarcoma) is a malignant tumor derived from fibrous connective tissue and characterized by immature proliferating fibroblasts or undifferentiated anaplastic spindle cells, and usually occurs in males aged 30–40. It originates in fibrous tissues of the bone and invades long or flat bones such as the femur, tibia and mandible. It also involves the periosteum and overlying muscle.
A 49-year-old female patient was diagnosed with cervical fibrosarcoma. The mass was detected at CT and then biopsied. The patient was referred for an FDG PET/CT (Fig. 52.1) to stage the disease. The scan showed focal FDG uptake in the cervical lesion, without any other evidence of disease.
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Case 53 Clinical Diagnosis: Large Soft Tissue Sarcoma
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b
c
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⊡ Fig. 53.1 FDG PET/CT (a: MIP image) showed increased FDG uptake in the left upper limb (black arrow on a, b and c, SUV max 11) (b: CT
scan; c: fused images), consistent with sarcoma. The cold area (white arrow) was consistent with necrosis
Case 53 Clinical Diagnosis: Large Soft Tissue Sarcoma
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⊡ Soft Tissue Sarcoma Clinical Case Soft tissue sarcomas are a group of neoplasms of mesodermal origin that constitutes approximately 1% of adult malignancies and 7% of pediatric malignancies. Most soft tissue sarcomas are sporadic with no specific etiologic agent. In some cases, however, a predisposing factor can be recognized. Soft tissue sarcomas arise predominantly in the abdomen and in the extremities. Usually the clinical presentation of patients with soft tissue sarcomas depends on the primary tumor site, while most patients with bone sarcoma present with localized pain. The diagnosis of sarcoma arises after a CT scan for soft tissue sarcomas, a MR scan for bone sarcomas and a targeted biopsy, while the disease staging is performed with satisfactory accuracy mainly with CT, especially for the evaluation of lung metastasis. The prognosis of these neoplasms is strongly related to several factors, among which it is important to remember the extent of the disease at diagnosis, the grade of the tumor, the age of the patient, the presence of microscopically positive margins after resection, the presence of metastasis at disease diagnosis and a long duration of symptoms before the diagnosis. The treatment of sarcomas relies basically on surgery, which is aimed at completely eradicating the disease. However, it is possible to increase the patient survival by combining surgery with chemotherapy and radiation therapy (adjuvant or neo-adjuvant) in order to facilitate surgical excision of large tumors or to consolidate local treatment after surgical resection.
An 89-year-old female patient was diagnosed with left upper limb large soft tissue sarcoma. The patient was referred for an FDG PET/CT (Fig. 53.1) to stage the disease. The scan showed FDG uptake in the mass, without any other evidence of disease. The mass was partially cold at FDG because of partial necrosis.
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Case 54 Clinical Diagnosis: Stump Appendicitis
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b
c
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⊡ Fig. 54.1 FDG PET/CT (a: MIP image) showed focal increased FDG uptake in the lower part of the cecum (black arrow on a, white arrow on b
and c, SUV max 13) (b: CT scan; c: fused images), consistent with stump appendicitis
Case 54
Clinical Diagnosis: Stump Appendicitis
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⊡ Stump Appendicitis Clinical Case Stump appendicitis is a delayed complication of incomplete appendectomy. Reinflammation of possible residual appendiceal tissue is possible although infrequent and should be considered in patients with right lower quadrant pain and a surgical history of appendectomy.
A 24-year-old female patient had been treated with appendectomy 7 years before. She presented with fever of unknown origin and was therefore referred for an FDG PET/CT (Fig. 54.1), showing focal FDG uptake in the lower part of the cecum. This was consistent with stump appendicitis.
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Case 55 Clinical Diagnosis: Bowel Transplantation with EBV Infection
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b
c
⊡ Fig. 55.1 FDG PET/CT (a: MIP image) showed diffused increased FDG uptake in the bowel (black arrow on a) (SUV max 5.9) (b: CT scan; c: fused images), consistent with viral infection 110
Case 55 Clinical Diagnosis: Bowel Transplantation with EBV Infection
⊡ EBV Infection in Posttransplant Patients Primary or reactivation EBV infection is an increasingly recognized complication occurring in transplant recipients that results from chronic immunosuppression. EBV infection may present as a broad spectrum of illnesses ranging from an asymptomatic state in which an increased viral load is detectable in the peripheral blood, to an inflammatory mononucleosistype syndrome, to lymphoma or posttransplant lymphoproliferative disease (PTLD), or, more rarely, spindle cell tumors. A number of reports have described an association between PTLD and a high EBV viral load in the blood as measured by PCR.
1
Clinical Case A 38-year-old male patient had been treated with bowel transplantation and presented with a persistent EBV infection. He was therefore referred for an FDG PET/CT (Fig. 55.1) to exclude lymphoproliferative disorders, showing diffuse intestinal and bone marrow FDG uptake consistent with posttransplant changes and anemia.
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Case 56 Clinical Diagnosis: Von Recklinghausen Disease
a
b
⊡ Fig. 56.1 FDG PET/CT (a: MIP image) showed increased bilateral FDG uptake in the lungs (black arrows on a, white arrow on b and c, SUV max 10–6) (b: CT scan; c: fused images) consis112
c
tent with von Recklinghausen disease. The abdominal area of increased tracer uptake is consistent with bowel activity
Case 56 Clinical Diagnosis: Von Recklinghausen Disease
1
⊡ Von Recklinghausen Disease Clinical Case Von Recklinghausen’s neurofibromatosis is also called von Recklinghausen disease or simply neurofibromatosis (NF). It is an autosomal dominant hereditary disorder. NF is the most common neurological disorder caused by a single gene. Patients develop multiple soft tumors (neurofibromas) and very often skin spots (freckling and café au lait). The tumors occur under the skin and throughout the nervous system.
A 41-year-old male patient presented with the diagnosis of von Recklinghausen disease. He was referred for an FDG PET/CT scan to assess the extension and the activity of the disease. The scan demonstrated highly increased bilateral tracer uptake in the lungs (Fig. 56.1) without evidence of other sites of disease.
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Case 57 Clinical Diagnosis: Wilms’ Tumor
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b
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⊡ Fig. 57.1 FDG PET/CT (a: MIP image) showed increased FDG uptake in the right kidney (black arrow on a, white arrow on b and c, SUV max 10.6) (b: CT scan; c: fused images) consistent
c
with Wilms’ tumor. The abdominal area of increased tracer uptake is consistent with bowel activity
Case 57 Clinical Diagnosis: Wilms’ Tumor
1
⊡ Wilms’ Tumor Clinical Case Wilms’ tumor or nephroblastoma is cancer of the kidneys that typically occurs in children, rarely in adults. Most nephroblastomas are unilateral, being bilateral in less than 5% of cases, although patients with Denys-Drash syndrome mostly have bilateral or multiple tumors. They tend to be encapsulated and vascularized tumors that do not cross the midline of the abdomen. In cases of metastasis it is usually to the lung. A rupture of Wilms’ tumor puts the patient at risk of hemorrhage and peritoneal dissemination of the tumor. In such cases, surgical intervention by a surgeon who is experienced in the removal of such fragile tumors is imperative.
A 3-year-old female patient presented with the diagnosis of a right renal mass. She was referred for an FDG PET/CT scan to characterize and stage the disease. The scan demonstrated an area of increased tracer uptake in the right kidney (Fig. 57.1) without evidence of other sites of disease. The patient was subsequently operated on, and histopathology showed Wilms’ tumor.
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Case 58 Clinical Diagnosis: Microcystic Tumor of the Pancreas
a
b
c
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⊡ Fig. 58.1 FDG PET/CT (a: MIP image) showed mild increased FDG uptake in the tail of the pancreas (white arrow on c, SUV max 2.2) (b: CT scan;
c: fused images), consistent with microcystic tumor of the pancreas (white arrow on b)
Case 58 Clinical Diagnosis: Microcystic Tumor of the Pancreas
1
⊡ Microcystic Tumor of the Pancreas Clinical Case Cystic tumors of the pancreas derive their name from the presence of fluid in the tumor. The fluid is produced by the lining of the tumor, which is abnormal and may give rise to a cancer in some patients. Cystic tumors of the pancreas are uncommon and constitute about 2% of all pancreatic tumors. Appropriate diagnosis of these tumors is important since surgical removal of the tumor is associated with a high cure rate. Unresected (not surgically removed) tumors particularly of the mucinous cystadenoma type can lead to invasive pancreatic cancer, a potentially fatal disorder. An important consideration is the separation of these tumors from a condition called pancreatic pseudocyst since cystic tumors are often misdiagnosed as pancreatic pseudocyst and inappropriately treated.
A 74-year-old female patient presented with the diagnosis of pancreatic mass at CT. She was referred for an FDG PET/CT scan to characterize and stage the disease. The scan demonstrated only mild tracer uptake in the pancreatic mass (Fig. 58.1). The patient was referred for a biopsy. Histopathology showed the presence of microcystic tumor of the pancreas.
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Cases 59–60 Clinical Diagnosis: Epilepsy
⊡ Fig. 59.1 FDG PET/CT showed an area of decreased FDG uptake in the left temporal lobe (white arrow), consistent with epileptic focus
⊡ Fig. 60.1 FDG PET/CT showed an area of decreased FDG uptake in the right frontal lobe (white arrow), consistent with epileptic focus
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Cases 59–60 Clinical Diagnosis: Epilepsy
1
⊡ Epilepsy Clinical Case 59 Epileptogenic zones can be localized by F-18 fluorodeoxyglucose positron emission tomography (FDG PET) and ictal single-photon emission computed tomography (SPECT). In medial temporal lobe epilepsy, the diagnostic sensitivity of FDG PET or ictal SPECT is excellent; however, the sensitivity of MRI is so high that the incremental sensitivity by FDG PET or ictal SPECT has yet to be proven. When MRI findings are ambiguous or normal, or discordant with those of ictal EEG, FDG PET and ictal SPECT are helpful for localization without the need for invasive ictal EEG. In neocortical epilepsy, the sensitivities of FDG PET or ictal SPECT are fair. However, because almost a half of the patients are normal on MRI, FDG PET and ictal SPECT are helpful for localization or at least for lateralization in these nonlesional epilepsies in order to guide the subdural insertion of electrodes.
A 13-year-old female patient presented with seizures. She was referred for an FDG PET/CT scan to possibly highlight the focus of the disease. The scan demonstrated an area of decreased tracer uptake in the left temporal lobe, consistent with the epileptic focus (Fig. 59.1).
Clinical Case 60 A 9-year-old male patient presented with seizures. She was referred for an FDG PET/CT scan to possibly highlight the focus of the disease. The scan demonstrated an area of decreased tracer uptake in the right frontal lobe, consistent with the epileptic focus (Fig. 60.1).
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Case 61 Clinical Diagnosis: Spindle Cell Carcinoma of the Prostate
a
b
c
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⊡ Fig. 61.1 FDG PET/CT (a: MIP image) showed increased tracer uptake in the prostate and in a large right external iliac adenopathy partially invading the adjacent bone and partially cold
(black arrows on a, white arrow on b and c, SUV max 9), consistent with prostate spindle cell carcinoma and secondary partially necrotic adenopathy
Case 61 Clinical Diagnosis: Spindle Cell Carcinoma of the Prostate
1
⊡ Spindle Cell Carcinoma Clinical Case Although relatively infrequent, spindle cell lesions of the prostate represent a diagnostically challenging and diverse array of entities. The majority of spindle cell lesions of the prostate are initially diagnosed on needle biopsy or transurethral resection (TUR) of the prostate. The presence of an elevated serum prostate-specific antigen (PSA) level, abnormal digital rectal examination or findings on imaging studies is nonspecific and may be associated with many of these lesions. Patient age is generally not helpful, although the differential diagnosis for patients under the age of 20 years most commonly includes rhabdomyosarcoma, which is generally not seen in an older population, and occasionally inflammatory myofibroblastic tumor. Owing to the rarity of these lesions, only a limited number of clinical or pathological studies have been performed that address the morphological spectrum and biological behavior of these entities.
A 71-year-old male patient was referred for prostatic biopsy after equivocal ultrasound. The result was spindle cell carcinoma of the prostate. The patient was referred for an FDG PET/CT (Fig. 61.1) to stage the disease. The scan showed increased tracer uptake in the prostate and in a right iliac adenopathy consistent with cancer localizations.
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Suggested Reading
122
Angouridakis N, Kafas P, Jerjes W, Triaridis S, Upile T, Karkavelas G, Nikolaou A (2011) Dermatofibrosarcoma protuberans with fibrosarcomatous transformation of the head and neck. Head Neck Oncol 4(3):5 Bauters F (1998) Vaquez disease. Diagnosis, course, treatment. Rev Prat 48(13):1483–1489, Review Bobba RK, Holly JS, Loy T, Perry MC (2011) Scar carcinoma of the lung: a historical perspective. Clin Lung Cancer 12(3):148–154 Bucher P, Chassot G, Zufferey G, Ris F, Huber O, Morel P (2005) Surgical management of abdominal and retroperitoneal Castleman’s disease. World J Surg Oncol 3:33 Cavalli F, Isaacson PG, Gascoyne RD, Zucca E (2001) MALT lymphomas. Hematology Am Soc Hematol Educ Program 241–58 PMID: 11722987 Chim C-S, Wong M, Fan Y (2008) Pulmonary interstitial amyloidosis complicating multiple myeloma. J Clin Oncol 26(3):504–506 Chiu K-M, Lin T-Y, Chu S-H, Lu C-W (2006) Managing sternal osteomyelitis with antibiotic bead implantation. Asian Cardiovasc Thorac Ann 14:e41–e42 Coselli JS, Köksoy C, LeMaire SA (1999) Management of thoracic aortic graft infections. Ann Thorac Surg 67(6):1990–1993; discussion 1997–1998 Cunha P, Luz Z, Seves I et al (2002) Malignant peritoneal mesothelioma – diagnostic and therapeutic difficulties. Acta Med Port 15:383–386 Dag A, Colak T, Turkmenoglu O, Sozutek A, Gundogdu R (2012) Phenol procedure for pilonidal sinus disease and risk factors for treatment failure. Surgery 151(1):113–117 Dillon CF, Hirsch R (2011) The United States National Health and Nutrition Examination Survey and the epidemiology of ankylosing spondylitis. Am J Med Sci 341(4):281–283 Fukasawa M, Maguchi H, Takahashi K, Katanuma A, Osanai M, Kurita A, Ichiya T, Tsuchiya T, Kin T (2010) Clinical features and natural history of serous cystic neoplasm of the pancreas. Pancreatology 10(6): 695–701 Gkouva L, Andrikoula M, Kontogeorgakos V, Papachristou DJ, Tsatsoulis A (2011) Active Paget’s disease of bone with normal biomarkers of bone metabolism: a case report and review of the literature. Clin Rheumatol 30(1):139–144 Gouliouris T, Aliyu SH, Brown NM (2010) Spondylodiscitis: update on diagnosis and management. J Antimicrob Chemother 65(Suppl 3):iii11–iii24 Hameed M, Dorfman H (2011) Primary malignant bone tumors – recent developments. Semin Diagn Pathol 28(1):86–101 Hansel DE, Herawi M, Montgomery E, Epstein JT (2007) Spindle cell lesions of the adult prostate. Mod Pathol 20:148–158
Hashemi-Sadraei N, Peereboom DM (2010) Chemotherapy in newly diagnosed primary central nervous system lymphoma. Ther Adv Med Oncol 2(4):273–292 Juéry P (2007) Avascular necrosis after a steroid injection. Can Med Assoc J 176(6):814; author reply 814 Kanegae K, Nakano I, Kimura K, Kaji H, Kuge Y, Shiga T, Zhao S, Okamoto S, Tamaki N (2008) Dual time point FDG-PET cannot increase the diagnostic accuracy for differentiation between pneumoconiotic nodules and lung cancer in patients with pneumoconiosis. J Nucl Med 49(Suppl 1):55 Kays DW (1992) Pediatric liver cysts and abscesses. Semin Pediatr Surg 1(2):107–114 Khan MS, ur Rehman S, Ali MA, Sultan B, Sultan S (2008) Infection in orthopedic implant surgery, its risk factors and outcome. J Ayub Med Coll Abbottabad 20(1):23–25 Khan S, Christopher-Stine L (2011) Polymyositis, dermatomyositis, and autoimmune necrotizing myopathy: clinical features. Rheum Dis Clin North Am 37(2):143–158 Lee DS, Lee SK, Lee MC (2001) Functional neuroimaging in epilepsy: FDG PET and ictal SPECT. J Korean Med Sci 16(6):689–696 Maillet-Vioud M, Narod S, Assouline D, Sobol H, Fischer G, Robert JM, Lenoir GM (1991) Genetics of neurofibromatosis: recent progress and prospects. Rev Neurol (Paris) 147(10):644–652 Majithia V, Geraci SA (2007) Rheumatoid arthritis: diagnosis and management. Am J Med 120(11):936–939 Mendenhall WM, Mendenhall CM, Reith JD, Scarborough MT, Gibbs CP, Mendenhall NP (2006) Pigmented villonodular synovitis. Am J Clin Oncol 29:548–550 Menichetti F (2009) Skin and skin tissue infections: main clinical patterns/pictures. Infez Med 17(Suppl 4): 30–36 Mohsen AH, McKendrick M (2003) Varicella pneumonia in adults. Eur Respir J 21:886–891 Mole TM, Glover J, Sheppard MN (1995a) Sclerosing mediastinitis: a report on 18 cases. Thorax 50: 280–283 Mole TM, Glover J, Sheppard MN (1995b) Sclerosing mediastinitis: a report on 18 cases. Thorax 50:280–283 Mole TM, Glover J, Sheppard MN (1995c) Sclerosing mediastinitis: a report on 18 cases. Thorax 50:280–283 Metzger ML, Dome JS (2005) Current therapy for Wilms’ tumor. Oncologist 10(10):815–826 O’Brien R, Pocock N, Torella F (2011) Wound infection after reconstructive arterial surgery of the lower limbs: risk factors and consequences. Surgeon 9(5):245–248 Ouazzani A, Bataille D, Raynal P, Vandueren E, Dubois E, Verhelst G (2011) Necrotizing fasciitis of the lower limb after venous surgery: cases studies and a review of the literature. Acta Chir Belg 111(2):103–106 Prabhakar HB, Rabinowitz CB, Gibbons FK, O’Donnell WJ, Shepard J-AO, Aquino SL (2008) Imaging features of sarcoidosis on MDCT, FDG PET, and PET/CT. AJR Am J Roentgenol 190:S1–S6
FDG: Rare Diseases
Park KS, Song BG, Ok KS, Park DW, Jung HJ, Kwak MO, Cho WH, Choi SK (2011) Primary cardiac angiosarcoma treated by complete tumor resection with cardiac reconstruction. Heart Lung 40(3):e41–e43 Reichert M, Bensadoun ES (2009) PET imaging in patients with coal worker’s pneumoconiosis and suspected malignancy. J Thorac Oncol 4(5):649–651 Reid-Lombardo KM, Khan S, Sclabas G (2010) Hepatic cysts and liver abscess. Surg Clin North Am 90(4): 679–697 Sayarlıoğlu M (2004) Remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome and malignancy. Eur J Gen Med 1(2):3–5 Sellheyer K (2011) Basal cell carcinoma: cell of origin, cancer stem cell hypothesis and stem cell markers. Br J Dermatol 164(4):696–711 Sharma M, Aronow WS, Patel L, Gandhi K, Desai H (2011) Hyperthyroidism. Med Sci Monit 17(4): RA85–RA91 Shafran SD (2002) Infective endocarditis and perivalvular abscess: a dangerous duo. CMAJ 167(1):38–39 Sia IG, Wieland ML (2011) Current concepts in the management of tuberculosis. Mayo Clin Proc 86(4):348–361
1
Tang XB, Qu RB, Bai YZ, Wang WL (2011) Stump appendicitis in children. J Pediatr Surg 46(1):233–236 Thompson GR III, Patterson TF (2008) Pulmonary aspergillosis. Semin Respir Crit Care Med 29(2):103–110 van Balen F, Smit W, Zuithoff N, Verheij T (2003) Clinical efficacy of three common treatments in acute otitis externa in primary care: randomised controlled trial. BMJ 327(7425):1201–1205 Vogel MN, Brodoefel H, Hierl T, Beck R, Bethge WA, Claussen CD, Horger MS (2007) Differences and similarities of cytomegalovirus and pneumocystis pneumonia in HIV-negative immunocompromised patients – thin section CT morphology in the early phase of the disease. Br J Radiol 80:516–523 Veyssier-Belot C, Cacoub P, Caparros-Lefebvre D et al (1996) Erdheim-Chester disease. Clinical and radiologic characteristics of 59 cases. Medicine (Baltimore) 75(3):157–169 Wilcox A, Bharadwaj P, Sharma OP (2000) Bone sarcoidosis. Curr Opin Rheumatol 12:321–330
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Chapter 2
11C-Choline: Rare Diseases
Case 62 Clinical Diagnosis: Hepatocellular Carcinoma . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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Case 63 Clinical Diagnosis: Multiple Myeloma . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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Case 64 Clinical Diagnosis: Paget’s Disease . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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Case 65 Clinical Diagnosis: Sarcoidosis . . . . . . . . . . . .
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Case 66 Clinical Diagnosis: Renal Cell Carcinoma . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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Suggested Reading. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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C. Nanni, S. Fanti, PET-CT: Rare Findings and Diseases, DOI 10.1007/978-3-642-24699-9_2, © Springer-Verlag Berlin Heidelberg 2012
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Case 62 Clinical Diagnosis: Hepatocellular Carcinoma
a
b
c
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⊡ Fig. 62.1 11C-Choline PET/CT (a: MIP image) showed increased tracer uptake in the first segment of the liver (white arrow on b and c)
(b: CT scan; c: fused images), consistent with disease persistence
Case 62 Clinical Diagnosis: Hepatocellular Carcinoma
⊡ Hepatocellular Carcinoma Hepatocellular carcinoma (HCC, also called malignant hepatoma) is the most common type of liver cancer. Most cases of HCC are secondary to either a viral hepatitis infection or cirrhosis. Treatment options for HCC and prognosis are dependent on many factors, but especially on tumor size and staging. Tumor grade is also important. High-grade tumors will have a poor prognosis, while low-grade tumors may go unnoticed for many years, as is the case in many other organs, such as the breast, where a ductal carcinoma in situ (or a lobular carcinoma in situ) may be present without any clinical signs and without correlate on routine imaging tests.
2
Clinical Case A 55-year-old female patient was affected by hepatocellular carcinoma. She was treated with thermoablation. After therapy the CT scan was equivocal for disease persistence. The patient was referred for an 11C-choline PET/CT scan to characterize the CT findings. The scan demonstrated increased uptake in the suspect lesion (Fig. 62.1). This was consistent with incomplete response to therapy.
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Case 63 Clinical Diagnosis: Multiple Myeloma
a
b
c
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⊡ Fig. 63.1 11C-Choline PET/CT (a: MIP image) showed increased tracer uptake in the sternum and in the fourth left rib (white arrows on MIP, b
and c) (b: CT scan; c: fused images), consistent with myelomatous bone lesions
Case 63 Clinical Diagnosis: Multiple Myeloma
2
⊡ Multiple Myeloma Clinical Case Multiple myeloma (MM) is a neoplastic disease caused by the uncontrolled proliferation of plasma cells within the bone marrow, causing bone marrow dysfunction, bone damages (lytic lesions), release of monoclonal protein in the blood stream (linked to organ damage) and immune system suppression. The incidence of MM is relatively low (3–4 new cases/100,000 in the USA), representing 1% of all malignant tumors, but increases to 9.5 new cases/100,000 among African Americans. Males are more frequently affected by MM compared to females (M:F = 3:2), with a peak of incidence at over 55 years. In more than 40% of patients, MM affects bones by producing interleukins activating osteoclasts. This process results in bone damage that can be diffuse (osteoporotic pattern) or focal (single or multiple lytic bone lesions), causing bone pain, pathological fractures, hypercalcemia, and hypercalciuria.
A 59-year-old male patient was affected by multiple myeloma. He was referred for an 11C-choline PET/CT scan to assess the extension of bone involvement. The scan demonstrated two focal areas of increased tracer uptake in the sternum and in the fourth left rib (Fig. 63.1), consistent with myelomatous lesions. No other areas of pathological increased uptake were detected.
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Case 64 Clinical Diagnosis: Paget’s Disease
a
b
c
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⊡ Fig. 64.1 11C-Choline PET/CT (a: MIP image) showed diffuse increased tracer uptake in the proximal femur (black arrow on a, white arrows
on b and c), corresponding to increased density at CT scan (b: CT scan; c: fused images), consistent with Paget’s disease
Case 64 Clinical Diagnosis: Paget’s Disease
2
⊡ Paget’s Disease Clinical Case Paget’s disease is a disorder that affects the normal remodeling process of bone. In the remodeling process, old bone is removed and new bone is formed. In patients with Paget’s disease, this process is altered. These patients have an excessive amount of bone removal followed by an even more excessive amount of new bone formation. Unfortunately, this increased rate of bone remodeling leads to new bone that is weaker, has more blood vessels, and is larger in size than normal bone. While most cases do not cause symptoms, some patients may develop pain, fractures, or even malignant transformation into sarcoma (bone tumor), although this is rare. Men are affected by Paget’s disease slightly more often than women (3:2). Paget’s disease is more common in patients of Northern European ancestry, most commonly in those from Great Britain. It is rare in the Asian and African populations. It is more common with increasing age, typically diagnosed in people in their 50s.
A 78-year-old male patient was affected by prostate cancer that was treated radically. He was referred for an 11C-choline PET/CT scan during the follow-up. The scan demonstrated an area of diffuse increased tracer uptake in the proximal femur, corresponding to increased density at CT scan (Fig. 64.1). This was subsequently proved to be Paget’s disease.
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Case 65 Clinical Diagnosis: Sarcoidosis
a
b
c
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⊡ Fig. 65.1 11C-Choline PET/CT (a: MIP image) showed diffuse increased tracer uptake in the right pulmonary hilum (black arrow on a, white
arrows on b and c) (b: CT scan; c: fused images), consistent with sarcoidosis
Case 65 Clinical Diagnosis: Sarcoidosis
2
⊡ Sarcoidosis Clinical Case Sarcoidosis is a disease in which abnormal collections of chronic inflammatory cells (granulomas) form as nodules in multiple organs. The cause of sarcoidosis is unknown. Granulomas most often appear in the lungs or the lymph nodes, but virtually any organ can be affected. Normally the onset is gradual. Sarcoidosis may be asymptomatic or chronic. It commonly improves or clears up spontaneously. More than two-thirds of people with lung sarcoidosis have no symptoms after 9 years. About 50% have relapses. About 10% develop serious disability. Lung scarring or infection may lead to respiratory failure and death.
A 62-year-old male patient was affected by prostate cancer that was treated radically. He was referred for an 11C-choline PET/CT scan during the follow-up. The scan demonstrated an area of increased tracer uptake in the right pulmonary hilum (Fig. 65.1). This was subsequently biopsied, and the final diagnosis was sarcoidosis.
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Case 66 Clinical Diagnosis: Renal Cell Carcinoma
a
b
c
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⊡ Fig. 66.1 11C-Choline PET/CT (a: MIP image) showed increased tracer uptake in the cortical left kidney (white arrows on b and c) (b: CT scan;
c: fused images), consistent with clear cell renal cancer
Case 66 Clinical Diagnosis: Renal Cell Carcinoma
2
⊡ Renal Cell Carcinoma Clinical Case Renal cell carcinoma (RCC) accounts for approximately 3% of adult malignancies and 90–95% of neoplasms arising from the kidney. This disease is characterized by a lack of early warning signs, diverse clinical manifestations, and resistance to radiation and chemotherapy. Increasingly, renal cell cancers are diagnosed at an earlier stage, and nephron-sparing surgery and thermal ablation are gaining acceptance as a treatment of choice for smaller tumors. Radical nephrectomy is the standard for larger and central tumors.
A 55-year-old male patient was referred for an 11C-choline PET/CT scan for characterizing a left kidney mass detected at ultrasound. The scan demonstrated an area of increased tracer uptake in the left cortical kidney (Fig. 66.1). He underwent nephrectomy, and the final diagnosis was clear cell cancer.
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Suggested Reading Bataille R, Harousseau JL (1997) Multiple myeloma. N Engl J Med 336(23):1657–1664 Bataille R, Manolagas SC, Berenson JR (2007) Pathogenesis and management of bone lesions in multiple myeloma. Hematol Oncol Clin North Am 11(2):349–361 Deveson Kell S (2011) Renal cell carcinoma: treatment options. Br J Nurs 20(9):536, 538–539
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El-Serag HB, Marrero JA, Rudolph L, Reddy KR (2008) Diagnosis and treatment of hepatocellular carcinoma. Gastroenterology 134(6):1752–1763 Gkouva L, Andrikoula M, Kontogeorgakos V, Papachristou DJ, Tsatoulis A (2011) Active Paget’s disease of bone with normal biomarkers of bone metabolism: a case report and review of the literature. Clin Rheumatol 30(1):139–144 Morgenthau AS, Iannuzzi MC (2011) Recent advances in sarcoidosis. Chest 139(1):174–182
Chapter 3
11C-Methionine: Rare Diseases
Case 67
Clinical Diagnosis: Adenocarcinoma of the Lung. . . . . . . . . . . . . . . . . . . . . . . . . . .
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Clinical Diagnosis: Brain Hemorrhage . . . . . . . . . . . . . . . . . . . . . . . . .
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Case 69
Clinical Diagnosis: Encephalitis . . . . . . .
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Cases 70–71
Clinical Diagnosis: Primary Hyperparathyroidism . . . . . . . . . . . . . . . .
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Clinical Diagnosis: Lymphoma of the Brain . . . . . . . . . . . . . . . . . . . . . . . . . .
146
Clinical Diagnosis: Soft Tissue Sarcoma . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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Suggested Reading. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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Case 68
Case 72
Case 73
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Case 67 Clinical Diagnosis: Adenocarcinoma of the Lung
a
b
⊡ Fig. 67.1 11C-Methionine PET/CT (a: MIP image) showed increased tracer uptake in the left pulmonary mass (b: CT scan; c: fused
138
c
images), consistent with adenocarcinoma. No lymph nodal metastases were detected
Case 67 Clinical Diagnosis: Adenocarcinoma of the Lung
3
⊡ Adenocarcinoma of the Lung Clinical Case Non-small-cell lung carcinoma (NSCLC) is any type of epithelial lung cancer other than small cell lung carcinoma (SCLC). As a class, NSCLCs are relatively insensitive to chemotherapy compared to small cell carcinoma. When possible, they are primarily treated by surgical resection with curative intent, although chemotherapy is increasingly being used both pre- (neoadjuvant chemotherapy) and postoperatively.
A 55-year-old male patient was referred for a 11C-methionine PET/CT scan for better characterization and then for accurately staging a left basal pulmonary mass detected on CT scan. The scan demonstrated an area of increased tracer uptake in the left pulmonary lesion (Fig. 67.1). He subsequently underwent left lower lobectomy, and the final diagnosis was adenocarcinoma.
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Case 68 Clinical Diagnosis: Brain Hemorrhage
a
b
⊡ Fig. 68.1 11C-Methionine PET/CT (a: CT scan; b: fused images) showed increased tracer uptake along the resected area, consistent with hemorrhage
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Case 68
Clinical Diagnosis: Brain Hemorrhage
3
⊡ Brain Hemorrhage Clinical Case A cerebral hemorrhage is a subtype of intracranial hemorrhage that occurs within the brain tissue itself. Intracerebral hemorrhage can be caused by brain trauma, or it can occur spontaneously in hemorrhagic stroke. Nontraumatic intracerebral hemorrhage is a spontaneous bleeding into the brain tissue. A cerebral hemorrhage is an intra-axial hemorrhage, that occurs within the brain tissue rather than outside of it. There are two main kinds of intra-axial hemorrhages: intraparenchymal and intraventricular hemorrhages. As with other types of hemorrhages within the skull, intraparenchymal bleeds are a serious medical emergency because they can increase intracranial pressure, which if left untreated can lead to coma and death. The mortality rate for intraparenchymal bleeds is over 40%.
A 35-year-old male patient was affected by right parietal glioblastoma that had been radically operated on recently. The patient was referred for an 11C-methionine PET/CT scan for assessing the possible presence of residual disease. The scan demonstrated an area of increased tracer uptake along the resected area (Fig. 68.1). This was consistent with hemorrhage, subsequently confirmed at MRI.
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Case 69 Clinical Diagnosis: Encephalitis
⊡ Fig. 69.1 11C-Methionine PET/CT (axial image) showed increased tracer uptake in the left brain (white arrow), consistent with acute inflammation
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Case 69 Clinical Diagnosis: Encephalitis
3
⊡ Encephalitis Clinical Cases Encephalitis, an inflammation of the brain parenchyma, presents as diffuse and/or focal neuropsychological dysfunction. Although it primarily involves the brain, the meninges are frequently involved (meningoencephalitis). Although bacterial, fungal, and autoimmune disorders can produce encephalitis, most cases are viral in origin. The incidence of encephalitis is 1 case per 200,000 population, with herpes simplex virus (HSV) being the most common cause.
A 36-year-old male patient suddenly developed neurological symptoms and therefore underwent brain MRI. This scan was equivocal, and the differential diagnosis between encephalitis and large malignancy was not possible. The patient was subsequently referred for an 11C-methionine PET/CT scan, showing a diffuse increased uptake in the left brain (Fig. 69.1). Considering the absence of focality, the scan was reported as consistent with acute inflammatory changes. This was subsequently clinically confirmed.
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Cases 70–71 Clinical Diagnosis: Primary Hyperparathyroidism
a
b
⊡ Fig. 70.1 11C-Methionine PET/CT (a: CT scan; b: fused images) showed focal increased tracer uptake in the upper mediastinum, consistent with ectopic parathyroid adenoma (white arrow on b)
a
b
⊡ Fig. 70.2 11C-Methionine PET/CT (a: CT scan; b: fused images) showed focal increased tracer uptake in the right laterocervical region, consistent with parathyroid adenoma
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Cases 70–71 Clinical Diagnosis: Primary Hyperparathyroidism
3
⊡ Primary Hyperparathyroidism Clinical Cases Primary hyperparathyroidism is a disorder of one or more of the parathyroid glands. The parathyroid gland(s) becomes overactive and secrete excess amounts of parathyroid hormone. As a result, the blood calcium rises to a level that is higher than normal (called hypercalcemia). An elevated calcium level can cause many short- and long-term complications. Primary hyperparathyroidism is different from secondary hyperparathyroidism, which occurs when the parathyroid glands overproduce parathyroid hormone in response to low blood levels of calcium; the low calcium level is caused by another condition, such as incorrect absorption from the intestines or kidney failure. Surgical removal of the hyperfunctioning gland is the therapy of choice.
Both patients were affected by primary hyperparathyroidism diagnosed on the basis of hematochemical exams. Both patients had negative neck ultrasound and MIBI scintigraphy. Both patients were referred for an 11C-methionine PET/CT (Figs. 70.1 and 70.2), detecting the parathyroid adenoma in both the cases. The patients were operated on based on the PET result, confirming the diagnosis.
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Case 72 Clinical Diagnosis: Lymphoma of the Brain
a
⊡ Fig. 72.1 11C-Methionine PET/CT detected a large area of increased tracer uptake (SUV max 10) in the right hemisphere corresponding to a
146
b
clear solid mass at CT (a: CT scan; b: fused images), consistent with lymphoma
Case 72 Clinical Diagnosis: Lymphoma of the Brain
3
⊡ Lymphoma of the Brain Clinical Case Primary cerebral lymphomas are rare. They represent less than 1% of all CNS tumors. It can occur at any age, but is more common in the elderly. It affects males and females equally. Geographically, the disease is found worldwide. This type of tumor spreads by infiltration of the cerebrospinal fluid and seeding within the central nervous system. In less than 10% of patients, distant metastases occur at sites such as the viscera, bones, and soft tissues. Primary cerebral lymphoma may be cured by radiotherapy and chemotherapy. Unfortunately, many of these tumors are incurable, and relapse occurs between 6 months and 2 years following initial treatment. Relapsed or recurrent disease generally has a very poor prognosis, often with death within a few months.
A 54-year-old male patient was referred for 11C-methionine PET/CT because of the diagnosis of lymphoma of the brain to grade the disease before therapy (Fig. 72.1).
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Case 73 Clinical Diagnosis: Soft Tissue Sarcoma
a
b
⊡ Fig. 73.1 11C-Methionine PET/CT (a: coronal CT, PET, fused images; b: sagittal CT, PET, fused images) showed increased tracer uptake in the
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right lower limb (red lines, SUV max 9), consistent with sarcoma
Case 73 Clinical Diagnosis: Soft Tissue Sarcoma
3
⊡ Soft Tissue Sarcoma Clinical Case Soft-tissue sarcomas are a group of neoplasms of mesodermal origin that constitute approximately 1% of adult and 7% of pediatric malignancies. Most soft-tissue sarcomas are sporadic with no specific etiologic agent. In some cases, however, a predisposing factor can be recognized. Soft tissue sarcomas arise predominantly in the abdomen and extremities. Usually the clinical presentation of patients with soft-tissue sarcomas depends on the primary tumor site, while most patients with bone sarcoma present with localized pain. The diagnosis of sarcoma arises after a CT scan for soft tissue sarcomas, a MR scan for bone sarcomas, and a targeted biopsy, while the disease staging is performed with satisfactory accuracy mainly with CT, especially for the evaluation of lung metastasis. The prognosis of these neoplasms is strongly related to several factors, among which it is important to remember the extent of the disease at diagnosis, the grade of the tumor, the age of the patient, the presence of microscopically positive margins after resection, the presence of metastasis at disease diagnosis, and a long duration of symptoms before the diagnosis. The treatment of sarcomas relies basically on surgery, which is aimed at completely eradicating the disease. However, it is possible to increase the patient survival by combining surgery with chemo- and radiation therapy (adjuvant or neoadjuvant) in order to facilitate surgical excision of large tumors or to consolidate local treatment after surgical resection.
An 81-year-old male patient was diagnosed with right lower limb soft tissue sarcoma. The patient was referred for an 11C-methionine PET/CT (Fig. 73.1) to grade the disease before radiotherapy and chemotherapy. The scan showed 11C-methionine uptake in the mass.
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Suggested Reading Bloch KC, Glaser C (2007) Diagnostic approaches for patients with suspected encephalitis. Curr Infect Dis Rep 9(4):315–322 Hameed M, Dorfman H (2011) Primary malignant bone tumors – recent developments. Semin Diagn Pathol 28(1):86–101
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Hashemi-Sadraei N, Peereboom DM (2010) Chemotherapy in newly diagnosed primary central nervous system lymphoma. Ther Adv Med Oncol 2(4):273–292 Johnson NA, Carty SE, Tublin ME (2011) Parathyroid imaging. Radiol Clin North Am 49(3):489–509, vi Travis WD, Travis LB, Devesa SS (1995) Lung cancer. Cancer 75(1 Suppl):191–202
Chapter 4
68Ga-Somatostatine Analogs: Rare Diseases
Case 74 Clinical Diagnosis: Cystic Serous Adenoma of the Pancreas. . . . . . . . . . . . . . . . . . . . . . . . . . . .
152
Case 75 Clinical Diagnosis: Chronic Pancreatitis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
154
Case 76 Clinical Diagnosis: Neuroendocrine Tumor of the Prostate . . . . . . . . . . . . . . . . . . . . .
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Suggested Reading. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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C. Nanni, S. Fanti, PET-CT: Rare Findings and Diseases, DOI 10.1007/978-3-642-24699-9_4, © Springer-Verlag Berlin Heidelberg 2012
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Case 74 Clinical Diagnosis: Cystic Serous Adenoma of the Pancreas
a
b
152
c
⊡ Fig. 74.1 68Ga DOTA NOC PET/CT (a: MIP image) did not show increased uptake in the pancreatic cystic lesion (white arrows on b and c) (b: CT scan; c: fused images)
Case 74 Clinical Diagnosis: Cystic Serous Adenoma of the Pancreas
4
⊡ Cystic Serous Adenoma of the Pancreas Clinical Case Cystic tumors of the pancreas derive their name from the presence of fluid in the tumor. The fluid is produced by the lining of the tumor, which is abnormal and may give rise to a cancer in some patients. Cystic tumors of the pancreas are uncommon and constitute about 2% of all pancreatic tumors. Appropriate diagnosis of these tumors is important since surgical removal of the tumor is associated with a high cure rate. Unresected (not surgically removed) tumors, particularly of the mucinous cystadenoma type, can lead to invasive pancreatic cancer, a potentially fatal disorder. An important consideration is the separation of these tumors from a condition called pancreatic pseudocyst since cystic tumors are often misdiagnosed as pancreatic pseudocyst and inappropriately treated.
A 56-year-old male patient was diagnosed with a pancreatic mass at ultrasound and was therefore referred for a 68Ga-DOTA NOC PET/CT to assess the presence of somatostatin receptors (Fig. 74.1). The scan result was negative. The patient was subsequently operated on, and the final diagnosis was cystic serous adenocarcinoma of the pancreas.
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Case 75 Clinical Diagnosis: Chronic Pancreatitis
a
b
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⊡ Fig. 75.1 68Ga DOTA NOC PET/CT (a: MIP image) showed diffuse increased uptake in the pancreas (black arrow on a and white arrows on b) (b: coronal view, CT, PET and fused images)
Case 75 Clinical Diagnosis: Chronic Pancreatitis
4
⊡ Chronic Pancreatitis Clinical Case Chronic pancreatitis is commonly defined as a continuing, chronic inflammatory process of the pancreas, characterized by irreversible morphological changes. This chronic inflammation can lead to chronic abdominal pain and/or impairment of endocrine and exocrine function of the pancreas. Chronic pancreatitis usually is envisioned as an atrophic fibrotic gland with dilated ducts and calcifications. However, findings on conventional diagnostic studies may be normal in the early stages of chronic pancreatitis, as the inflammatory changes can be seen only by histological examination.
A 58-year-old female patient had been previously radically treated for neuroendocrine tumor of the pancreas. She was referred for a 68Ga DOTA NOC PET/CT (Fig. 75.1) during the follow-up. The scan showed a diffuse increased tracer uptake in the whole residual pancreas. Subsequently, the diagnosis of chronic pancreatitis was made.
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Case 76 Clinical Diagnosis: Neuroendocrine Tumor of the Prostate
a
b
⊡ Fig. 76.1 68Ga DOTA NOC PET/CT (a: MIP
156
image) showed focal increased tracer uptake in multiple bones consistent with secondary lesions (white arrows on b and c). Several areas
c
of increased CT density in bones did not present significant tracer uptake (yellow arrows on b and c) (b: CT scan, c: fused images)
Case 76 Clinical Diagnosis: Neuroendocrine Tumor of the Prostate
4
⊡ Neuroendocrine Prostate Tumor Clinical Case Neuroendocrine differentiation in prostatic carcinoma can take the form of a pure neuroendocrine tumor that is a small-cell carcinoma (SCC) or a carcinoid tumor of the prostate. Pure neuroendocrine tumors constitute a small percentage of prostatic malignancies with a poor prognosis. Because of its rarity, there is a relative scarcity of information on the clinicopathological behavior and optimum treatment strategies for this tumor. The prognosis of pure neuroendocrine prostatic carcinoma is dependent on the differentiation. Well-differentiated carcinoid tumors have a better outcome than SCC, which has a poor prognosis, with a fatal outcome within 1 year in most cases.
A 65-year-old male patient was referred for a 68Ga DOTA NOC PET/CT (Fig. 76.1) to stage a neuroendocrine tumor of the prostate. The scan showed focal increased tracer uptake in multiple bones consistent with secondary lesions. Interestingly, several areas of increased CT density in bones did not present significant tracer uptake. This was probably consistent with de-differentiated secondary lesions.
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Suggested Reading Fukasawa M, Maguchi H, Takahashi K, Katanuma A, Osanai M, Kurita A, Ichiya T, Tsuchiya T, Kin T (2010) Clinical features and natural history of serous cystic neoplasm of the pancreas. Pancreatology 10(6):695–701
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Ketata S, Ketata H, Fakhfakh H, Sahnoun A, Bahloul A, Boudawara T, Mhiri MN (2006) Pure primary neuroendocrine tumor of the prostate: a rare entity. Clin Genitourin Cancer 5(1):82–84 Pezzilli R (2009) Etiology of chronic pancreatitis: has it changed in the last decade? World J Gastroenterol 15(38):4737–4740
Chapter 5
FDG: Rare Findings
Case 77
Clinical Diagnosis: Portal Thrombosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
162
Clinical Diagnosis: Acute Pulmonary Alveolitis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
164
Clinical Diagnosis: Inflammatory Abdominal Aortic Aneurysm. . . . . . . . . . . . . .
166
Clinical Diagnosis: Cavernous Hemangioma . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
168
Clinical Diagnosis: Liver Hemangioma . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
170
Clinical Diagnosis: Renal Angiomyolipoma . . . . . . . . . . . . . . . . . . . . . . . . .
172
Clinical Diagnosis: Kidney Stone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
174
Case 84
Clinical Diagnosis: Cholecystitis. . . . . . . . . . .
176
Case 85
Clinical Diagnosis: Cholesterolosis of the Gallbladder . . . . . . . . . . . . . . . . . . . . . . . .
178
Clinical Diagnosis: Metformin and Colitis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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Case 87
Clinical Diagnosis: Corpus Luteum . . . . . . . .
182
Case 88
Clinical Diagnosis: Pulmonary Heart . . . . . .
184
Case 89
Clinical Diagnosis: Infection of Central Venous Catheter . . . . . . . . . . . . . . .
186
Clinical Diagnosis: Double Ureter . . . . . . . . .
188
Case 78
Case 79
Case 80
Case 81
Case 82
Case 83
Case 86
Case 90
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Case 91
Clinical Diagnosis: Interstitial Pulmonary Edema . . . . . . . . . . . . . . . . . . . .
190
Case 92
Clinical Diagnosis: Septic Pulmonary Embolism . . . . . . . . . . . . . . . . . . . . .
192
Case 93
Clinical Diagnosis: Subcutaneous Emphysema . . . . . . . . . . . . . . . . . . . . . .
194
Case 94
Clinical Diagnosis: Inguinal Hernia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
196
Case 95
Clinical Diagnosis: Frontal Hematoma . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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Case 96
Clinical Diagnosis: Chronic Atrial Fibrillation . . . . . . . . . . . . . . . . . . . . . . . .
200
Case 97
Clinical Diagnosis: Large Uterine Fibromas . . . . . . . . . . . . . . . . . . . . . . . . . .
202
Case 98
Clinical Diagnosis: Respiratory Failure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
204
Case 99
Clinical Diagnosis: Recent Bone Fracture . . . . . . . . . . . . . . . . . . . . . . . . . . . .
206
Case 100
Clinical Diagnosis: Bone Infarct . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
208
Case 101
Clinical Diagnosis: Pulmonary Infarction . . . . . . . . . . . . . . . . . . . . . . . . . . . .
210
Cases 102–103 Clinical Diagnosis: Aortic Graft Infection . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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Case 104
Clinical Diagnosis: Hip Prosthesis Infection . . . . . . . . . . . . . . . . . . . . . . . . .
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Case 105
Clinical Diagnosis: Intraductal Papillary Mucinous Neoplasm (IPMN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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Case 106
Clinical Diagnosis: Aortic Graft Leakage . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
220
Case 107
Clinical Diagnosis: Mastoiditis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
222
Case 108
Clinical Diagnosis: Pulmonary Microembolism . . . . . . . . . . . . . . . . . . . . . .
224
Case 109
Clinical Diagnosis: Avascular Necrosis of the Head of the Humerus . .
226
Cases 110–111 Clinical Diagnosis: Nonspecific Interstitial Pneumonia (NSIP). . . . . . . .
228
Case 112
Clinical Diagnosis: Muscular Uptake . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
232
Case 113
Clinical Diagnosis: Muscular Lipoma . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
234
Case 114
Clinical Diagnosis: Constrictive Pericarditis . . . . . . . . . . . . . . . . . . . . . . . . .
236
Case 115
Clinical Diagnosis: Benign Asbestos Pleural Disease . . . . . . . . . . . . . . . . .
238
Case 116
Clinical Diagnosis: Pleuropericarditis in Inflammatory Bowel Disease (IBD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
240
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FDG: Rare Findings
Case 117
Clinical Diagnosis: Bacterial Pneumonia . . . . . . . . . . . . . . . . . . . . . . . . . . . .
242
Case 118
Clinical Diagnosis: Postradiotherapy Changes . . . . . . . . . . . . . . . . . . . . . .
244
Case 119
Clinical Diagnosis: Xanthogranulomatous Lymphadenitis . . . . . . . . . . .
246
Case 120
Clinical Diagnosis: Knee Prosthesis: Physiological Biodistribution . . .
248
Case 121
Clinical Diagnosis: Nodular Radiation Pneumonitis . . . . . . . . . . . . . . . . .
250
Case 122
Clinical Diagnosis: Spina Bifida. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
252
Case 123
Clinical Diagnosis: Spondylolisthesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
254
Case 124
Clinical Diagnosis: Rib Fracture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
256
Case 125
Clinical Diagnosis: Inferior Vena Cava Thrombosis. . . . . . . . . . . . . . . . . . .
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Case 126
Clinical Diagnosis: Duodenal Ulcer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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Case 127
Clinical Diagnosis: Shingles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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Suggested Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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5
Case 77 Clinical Diagnosis: Portal Thrombosis
a
b
c
162
⊡ Fig. 77.1 FDG PET/CT (a: MIP image) showed focal increased tracer uptake in the portal tree, consistent with portal thrombosis (black arrow
on a, white arrows on b and c) (b: CT scan, c: fused images)
Case 77 Clinical Diagnosis: Portal Thrombosis
5
⊡ Portal Thrombosis Clinical Case Portal vein thrombosis is a form of venous thrombosis affecting the hepatic portal vein, which can lead to portal hypertension and reduction in the blood supply to the liver. Causes can include pancreatitis, cirrhosis, diverticulitis, and cholangiocarcinoma. It is also a known complication of splenectomy. Treatments include anticoagulants, shunts, bypass surgery, and transplants. It also can be medically managed with blood thinners.
A 56-year-old female patient was referred for an FDG PET/CT scan (Fig. 77.1) during the follow-up of a dedifferentited pancreatic neuroendocrine tumor. She was also affected by portal thrombosis. The scan was negative for neuroendocrine tumor relapse, but areas of increased uptake in the portal tree were detected. This was consistent with thrombosis.
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Case 78 Clinical Diagnosis: Acute Pulmonary Alveolitis
a
b
c
164
⊡ Fig. 78.1 FDG PET/CT (a: MIP image) showed mild and diffuse tracer uptake in both the lungs, consistent with alveolar inflammation (b: CT scan, c: fused images)
Case 78 Clinical Diagnosis: Acute Pulmonary Alveolitis
5
⊡ Acute Pulmonary Alveolitis Clinical Case Acute pulmonary alveolitis is an acute inflammation involving exudate into the pulmonary alveoli and impaired gas exchange such as occurs in several interstitial lung diseases, including diffuse alveolar damage, druginduced lung disease, and acute immunological injury.
A 35-year-old male patient was referred for an FDG PET/CT scan (Fig. 78.1) after chemotherapy for NHL. The scan was negative for malignancy, but mild diffuse tracer uptake was noticed in both lungs. This was consistent with acute pulmonary alveolitis.
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Case 79 Clinical Diagnosis: Inflammatory Abdominal Aortic Aneurysm
a
b
166
⊡ Fig. 79.1 FDG PET/CT (a: MIP image) showed increased tracer uptake in the abdominal aorta (black arrow on a and on PET image, white arrow
on PET/CT image) consistent with inflammatory aneurysm (b: coronal view CT, PET, fused images)
Case 79
⊡ Inflammatory Aneurysm
Clinical Diagnosis: Inflammatory Abdominal Aortic Aneurysm
Abdominal
5
Aortic
Inflammatory abdominal aortic aneurysm (AAA) accounts for 5–10% of all cases of AAA and differs from typical atherosclerotic AAA in many important ways. Although both inflammatory and atherosclerotic AAAs most commonly affect the infrarenal portion of the abdominal aorta, patients with the inflammatory variant are younger and usually symptomatic, chiefly from back or abdominal pain. Unlike patients with atherosclerotic AAA, most with the inflammatory variant have an elevated erythrocyte sedimentation rate or abnormalities of other serum inflammatory markers. Computed tomography and magnetic resonance imaging are both sensitive for demonstrating the cuff of soft tissue inflammation surrounding the aneurysm that is characteristic of inflammatory AAA. In contrast to atherosclerotic AAA, the inflammatory variant is characterized pathologically by marked thickening of the aneurysm wall, fibrosis of the adjacent retroperitoneum, and rigid adherence of the adjacent structures to the anterior aneurysm wall. An extraordinary expansion of the adventitia due to inflammation also distinguishes inflammatory from atherosclerotic AAA. Although the pathogenesis of inflammatory AAA appears to involve an immune response localized to the vessel wall, the etiology of the inflammatory reaction is unknown. Inflammatory AAA is almost never associated with inflammation of other arteries. Male sex and smoking, the main risk factors for atherosclerotic AAA, are even stronger risk factors for the inflammatory variant. Smoking cessation is the first step of medical therapy. Corticosteroids or immunosuppressive therapies may also have roles. Although inflammatory AAA appears less likely to rupture than atherosclerotic AAA, surgical intervention appears prudent once the diameter of the aneurysm exceeds 5.5 cm.
Clinical Case A 71-year-old male patient was referred for an FDG PET/CT scan (Fig. 79.1) during the follow-up for colon cancer. The scan was negative for malignancy, but an area of increased uptake in the abdominal aorta was detected (Fig. 79.1). At CT scan the diameter of the vessel had increased. Subsequent imaging controls were consistent with inflammatory abdominal aortic aneurysm.
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Case 80 Clinical Diagnosis: Cavernous Hemangioma
a
b
168
⊡ Fig. 80.1 FDG PET/CT (a: CT scan; b: fused images) showed an area of no uptake in the left parietal lobe (white arrow), consistent with cavernous hemangioma
Case 80
Clinical Diagnosis: Cavernous Hemangioma
5
⊡ Cavernous Hemangioma Clinical Case Cavernous angioma, also known as cerebral cavernous malformation (CCM), cavernous hemangioma, and cavernoma, is a vascular disorder that alternately has been classified as neoplastic or hamartomatous. It is characterized by grossly dilated blood vessels with a single layer of endothelium and an absence of neuronal tissue within the lesions. These thinly walled vessels resemble sinusoidal cavities filled with stagnant blood. Blood vessels in patients with CCM can range from a few millimeters to several centimeters in diameter. Most lesions occur in the brain, but any organ can be involved.
A 35-year-old male patient was referred for an FDG PET/CT scan (Fig. 80.1) after chemotherapy and radiotherapy for Ewing’s sarcoma. The scan was negative for malignancy, but a completely cold area was detected in the left parietal lobe. This was subsequently proved to be a cavernous hemangioma.
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Case 81 Clinical Diagnosis: Liver Hemangioma
a
b
c
170
⊡ Fig. 81.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) showed an area of mild increased uptake in the liver, subsequently proved to be hemangioma (white arrows)
Case 81
Clinical Diagnosis: Liver Hemangioma
5
⊡ Liver Hemangioma Clinical Case Cavernous hemangioma is the most common primary liver tumor; its occurrence in the general population ranges from 0.4% to 20%. Cavernous hemangiomas arise from the endothelial cells that line the blood vessels, and consist of multiple, large vascular channels lined by a single layer of endothelial cells and supported by collagenous walls. These tumors are frequently asymptomatic and incidentally discovered at imaging, surgery, or autopsy. Hemangiomas are uncommon in cirrhotic livers; the fibrotic process in the cirrhotic liver may prohibit their development.
A 45-year-old female patient was referred for an FDG PET/CT scan (Fig. 81.1) during the follow-up for breast cancer. The scan was negative for malignancy, but an area of very mild increased uptake was detected in the liver. This was subsequently proved to be a liver hemangioma.
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Case 82 Clinical Diagnosis: Renal Angiomyolipoma
a
b
c
⊡ Fig. 82.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) showed an area of no uptake in the lower lobe of the right kidney (white arrows) 172
Case 82
Clinical Diagnosis: Renal Angiomyolipoma
5
⊡ Renal Angiomyolipoma Clinical Case A renal angiomyolipoma (AML) is a benign renal neoplasm composed of vascular, smooth muscle, and fat elements that often has characteristic imaging appearances. The majority of angiomyolipomas are sporadic (80%) and are typically identified in adults (mean age of presentation 43 years), with a strong female predilection (F:M 4:1). The remaining 20% are seen in association with phakomatoses, the vast majority in the setting of tuberous sclerosis, although they have also been described in the setting of von Hippel Lindau syndrome (vHL) and neurofibromatosis type 1 (NF1). In these cases they present earlier (usually identified by the age of 10 years), are larger, and far more numerous. They are more likely to be fat-poor, which accounts for their earlier presentation. Angiomyolipomas are often found incidentally when the kidneys are imaged for other reasons or as part of screening in patients with tuberous sclerosis.
A 45-year-old female patient was referred for an FDG PET/CT scan (Fig. 82.1) during the follow-up for rectal cancer. The scan was negative for malignancy, but an area of no uptake in the lower lobe of the right kidney was detected. This corresponded to an area of decreased density at CT, consistent with angiomyolipoma.
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Case 83 Clinical Diagnosis: Kidney Stone
a
b
⊡ Fig. 83.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) showed an obstacle in the left ureter deflux (black arrow on a and white arrow 174
c
on b and c). At the CT scan the kidney was enlarged
Case 83
Clinical Diagnosis: Kidney Stone
5
⊡ Kidney Stone Clinical Case A kidney stone, also known as a renal calculus, is a solid concretion or crystal aggregation formed in the kidneys from dietary minerals in the urine. Urinary stones are typically classified by their location in the kidney (nephrolithiasis), ureter (ureterolithiasis), or bladder (cystolithiasis), or by their chemical composition (containing calcium, struvite, uric acid, or other compounds). Kidney stones are a significant source of morbidity. Eighty percent of those with kidney stones are men. Men most commonly experience their first episode between 30 and 40 years, while for women the age at first presentation is somewhat later.
A 73-year-old male patient was referred for an FDG PET/CT scan (Fig. 83.1) during the follow-up for rectal cancer. The scan was negative for malignancy, but an obstacle in the left ureter deflux was noticed. At the CT scan the kidney was enlarged. The patient had experienced referred pain in the left flank the night before. The final diagnosis was radiotransparent lithiasis.
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Case 84 Clinical Diagnosis: Cholecystitis
a
b
⊡ Fig. 84.1 FDG PET/CT (a: MIP; b: CT scan; 176
c: fused images) showed an area of increased tracer uptake in the wall of the gallbladder.
c
Furthermore, several small hypermetabolic bilateral mediastinal lymph nodes were detected (white arrows)
Case 84 Clinical Diagnosis: Cholecystitis
5
⊡ Cholecystitis Clinical Case Cholecystitis is an inflammation of the gallbladder. It usually presents as a pain in the right upper quadrant. This is usually a constant, severe pain. During the initial stages, the pain may be felt in an area totally separate from the site of pathology, known as referred pain. In cholecystitis the referred pain may occur in the right scapula region. Sonography is a sensitive and specific modality for diagnosis of acute cholecystitis; the adjusted sensitivity and specificity for diagnosis of acute cholecystitis are 88% and 80%, respectively. The two major diagnostic criteria are cholelithiasis and sonographic Murphy’s sign. Minor criteria include gallbladder wall thickening greater than 3 mm, pericholecystic fluid, and gallbladder dilatation. The reported sensitivity and specificity of CT scan findings are in the range of 90–95%. CT is more sensitive than ultrasonography in the depiction of pericholecystic inflammatory response and in localizing pericholecystic abscesses, pericholecystic gas, and calculi outside the lumen of the gallbladder. CT cannot see noncalcified gallbladder calculi and cannot assess for a Murphy’s sign.
A 62-year-old female patient was referred for an FDG PET/CT scan (Fig. 84.1) during the follow-up for colon cancer. The scan was negative for malignancy, but an area of increased tracer uptake was detected in the wall of the gallbladder. This was consistent with inflammation. Furthermore, several small hypermetabolic bilateral mediastinal lymph nodes were detected, consistent with inflammatory changes.
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Case 85 Clinical Diagnosis: Cholesterolosis of the Gallbladder
a
b
⊡ Fig. 85.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) showed an area of increased uptake in the abdomen consistent with residual lymphomatous disease (red arrow). Furthermore, 178
c
an area of mild increased tracer uptake was detected in the wall of the gallbladder (white arrows)
Case 85 Clinical Diagnosis: Cholesterolosis of the Gallbladder
5
⊡ Cholesterolosis Clinical Case In surgical pathology cholesterolosis of the gallbladder or gallbladder cholesterolosis (more commonly strawberry gallbladder) is a change in the gallbladder wall due to excess cholesterol. The name strawberry gallbladder comes from the typically stippled appearance of the mucosal surface on gross examination, which resembles the appearance of a strawberry. It is not necessarily tied to cholelithiasis (gallstones) or cholecystitis (inflammation of the gallbladder).
A 53-year-old female patient was referred for an FDG PET/CT scan (Fig. 85.1) after two cycles of chemotherapy for NHL. The scan was still positive for lymphoma since an area of increased uptake was present in the abdomen. Furthermore, an area of mild increased tracer uptake was detected in the wall of the gallbladder. This was subsequently proved to be cholesterolosis.
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Case 86 Clinical Diagnosis: Metformin and Colitis
a
b
180
⊡ Fig. 86.1 FDG PET/CT (a: MIP; b: CT scan; c:fused images) showed an area of increased uptake in the right lung consistent with
c
malignancy (red arrow). Furthermore, an area of diffuse increased tracer uptake was detected in the colon (white arrows)
Case 86 Clinical Diagnosis: Metformin and Colitis
5
⊡ Metformin and Colitis Clinical Case Metformin Oral is a diabetes drug used to normalize the body’s response to insulin, which can prevent hyperglycemia. Metformin taken orally can cause side effects. Most of Metformin Oral’s side effects are mild and temporary. The most common are: nausea, stomach pain, upset stomach, diarrhea, and metallic taste in the mouth.
A 67-year-old male patient was referred for an FDG PET/CT scan (Fig. 86.1) to stage a right lung squamous cell carcinoma. The scan was positive in the right pulmonary mass without any distant metastasis. Furthermore, diffuse and intense FDG uptake was noticed in the colon. This was consistent with severe colitis, probably related to the administration of metformin as antidiabetic therapy.
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Case 87 Clinical Diagnosis: Corpus Luteum
a
b
182
c
⊡ Fig. 87.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) showed an area of increased uptake in the right ovary (black arrow on a and white arrows on b and c)
Case 87 Clinical Diagnosis: Corpus Luteum
5
⊡ Corpus Luteum Clinical Case The corpus luteum is a temporary endocrine structure in mammals, involved in production of relatively high levels of progesterone and moderate levels of estradiol and inhibin A. Since it has inflammatory characteristics, it can be FDG PET positive.
A 32-year-old female patient was referred for an FDG PET/CT scan (Fig. 87.1) during the follow-up of left ovarian cancer, which was treated surgically. The scan was negative for malignancy, but an area of focal and increased tracer uptake was present in the right ovary. A subsequent ultrasound proved the presence of a large corpus luteum.
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Case 88 Clinical Diagnosis: Pulmonary Heart
a
b
c
⊡ Fig. 88.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) showed significantly increased FDG uptake in the heart walls, especially the right ventricle wall (white arrow) 184
Case 88 Clinical Diagnosis: Pulmonary Heart
5
⊡ Pulmonary Heart Clinical Case Pulmonary heart is a heart disease resulting from a lung disorder. It is a complication of lung disorders where the blood flow into the lungs is slowed or blocked, causing increased lung pressure. The right side of the heart has to pump harder to push against the increased pressure, and this can lead to enlargement of the heart muscle and other problems. Ultimately, congestive heart failure of the right side of the heart can result. Other chronic lung conditions that can cause pulmonary heart disease are pulmonary hypertension, cystic fibrosis, and advanced emphysema.
A 77-year-old female patient was followed for idiopathic pulmonary hypertension. At the CT scan a left lung nodule was noticed. She was referred for an FDG PET/CT scan (Fig. 88.1), which was negative, in the lungs. However, there was significantly increased FDG uptake in the heart walls (especially the right ventricle walls), and the heart was enlarged. This was consistent with pulmonary heart secondary to pulmonary hypertension.
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Case 89 Clinical Diagnosis: Infection of Central Venous Catheter
a
b
c
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⊡ Fig. 89.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) showed two areas of increased tracer uptake were detected along the central
venous catheter (black arrow on a and white arrow on b and c)
Case 89 Clinical Diagnosis: Infection of Central Venous Catheter
5
⊡ Infection of Central Venous Catheter Clinical Case Central venous catheters (CVCs) are commonly used in critically ill patients for the administration of fluids, medications, blood products, and parenteral nutrition, for the insertion of a transvenous pacing electrode, and to monitor hemodynamic status. The use of catheters is common in critically ill patients; in the EPIC study, 78% of critically ill patients had some form of CVC inserted. Central venous catheterization may cause different complications, including infection, hemorrhage, and thrombosis. Interest in catheter-related infection lies in the mortality and the costs involved.
An 8-year-old male patient was affected by HD. He was referred for an FDG PET/ CT scan (Fig. 89.1) in the course of chemotherapy to early assess the response to therapy. The scan demonstrated a complete response, but two areas of increased tracer uptake were detected along the central venous catheter. This was subsequently removed and showed infection.
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Case 90 Clinical Diagnosis: Double Ureter
a
b
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⊡ Fig. 90.1 FDG PET/CT (a: MIP; b: coronal view of the CT scan, PET, and fused images) showed increased tracer persistence in the right
abdomen (black and white arrows), indicating a double ureter
Case 90
Clinical Diagnosis: Double Ureter
5
⊡ Double Ureter Clinical Case Double ureter is the existence of a second ureter on one side that may be a complete connection from the kidney to the bladder or a partial tube forming a blind pouch. Most are asymptomatic, but some are accompanied by ectopic ureterocele. It is also called ureteral duplication.
A 20-year-old male patient was in followed up for HD. He was referred for an FDG PET/CT scan (Fig. 90.1), resulting negative for malignancy. However, two areas of increased tracer persistence were detected in the right abdomen, indicating a double ureter.
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Case 91 Clinical Diagnosis: Interstitial Pulmonary Edema
a
b
c
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⊡ Fig. 91.1 FDG PET/CT (a: MIP; b: CT scan, c: fused images) showed the presence of a single bone myelomatous lesion in the right scapula
(red arrow ) and mild and diffuse uptake in both the lungs (black arrow on a and white arrow on b and c)
Case 91
Clinical Diagnosis: Interstitial Pulmonary Edema
5
⊡ Interstitial Pulmonary Edema Clinical Case Pulmonary edema is a common clinical and pathologic condition. Hemodynamic disturbances or a change in microvascular permeability can cause pulmonary edema. When the capacity of the lymphatics to drain the interstitial fluid is exceeded, interstitial edema develops. There is loss of lung compliance. When there is a further rise in interstitial pressure, the tight junctions between the alveolar epithelial cells open and fluid moves into the alveolar spaces causing alveolar edema. The ventilation stops at this stage. Chronic edema predisposes to infection. Alveolar edema fluid is a good culture media. Secondary pneumonia may occur. There is impairment of normal respiratory function. Interstitial pulmonary edema represents the earliest phase and is an exaggeration of the normal process of filtration.
A 56-year-old male patient was affected by heart failure and was referred for an FDG PET/CT scan (Fig. 91.1) to stage recently diagnosed multiple myeloma. The scan demonstrated the presence of a single bone myelomatous lesion in the right scapula, and mild and diffuse uptake in both lungs. This was consistent with interstitial pulmonary edema, confirmed at HRCT.
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Case 92 Clinical Diagnosis: Septic Pulmonary Embolism
a
b
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⊡ Fig. 92.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) showed the presence of a few tiny areas of mild increased uptake that were
c
present peripherally in both lungs (white arrows on b and c)
Case 92
Clinical Diagnosis: Septic Pulmonary Embolism
5
⊡ Septic Pulmonary Embolism Clinical Case Septic pulmonary embolism (SPE) is an uncommon disorder that generally presents with an insidious onset of fever, respiratory symptoms, and lung infiltrates. Clinical and radiological features at presentation are usually nonspecific, and the diagnosis of this disorder is frequently delayed. Historically, SPE has been associated with risk factors such as IV drug use, pelvic thrombophlebitis, and suppurative processes in the head and neck. However, increasing use of indwelling catheters and devices as well as increasing numbers of immunocompromised patients has changed the epidemiology and clinical manifestations of SPE. In SPE, the embolic blood clot that leads to an infarction in the pulmonary vasculature also contains microorganisms that incite a focal abscess.
A 44-year-old male patient was affected by endocarditis on the prosthetic valve and was referred for an FDG PET/CT scan (Fig. 92.1) after 3 months of antibiotic therapy to assess the presence of residual inflammation. The scan was negative in the heart, but a few tiny areas of mild increased uptake were present peripherally in both lungs. This was subsequently proved to be septic pulmonary embolism.
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Case 93 Clinical Diagnosis: Subcutaneous Emphysema
a
b
⊡ Fig. 93.1 FDG PET/CT (a: MIP; b: CT scan; 194
c: fused images) demonstrated an area of focal increased uptake (red arrow) consistent with disease relapse and inflammation of the
c
tracheostomy (blue arrow). Furthermore, several cold areas in the neck corresponding to decreased density at CT were detected (white arrow)
Case 93 Clinical Diagnosis: Subcutaneous Emphysema
5
⊡ Subcutaneous Emphysema Clinical Case Subcutaneous emphysema, sometimes abbreviated SCE or SE and also called tissue emphysema, or Sub Q air, occurs when gas or air is present in the subcutaneous layer of the skin. Since the air generally comes from the chest cavity, subcutaneous emphysema usually occurs on the chest, neck, and face, where it is able to travel from the chest cavity along the fascia. Subcutaneous emphysema has a characteristic crackling feel to the touch; this sensation of air under the skin is known as subcutaneous crepitation.
A 69-year-old male patient was recently operated on for laryngectomy for malignancy and was referred for an FDG PET/CT scan (Fig. 93.1) after the completion of therapy. The scan demonstrated a disease relapse and inflammation of the tracheostomy. Furthermore, several cold areas in the neck corresponding to decreased density at CT were detected. These were consistent with subcutaneous emphysema.
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Case 94 Clinical Diagnosis: Inguinal Hernia
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b
c
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⊡ Fig. 94.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) demonstrated an area of increased tracer uptake in the left inguinal
region. This was related to left inguinal hernia (black arrow on a and white arrow on b and c)
Case 94 Clinical Diagnosis: Inguinal Hernia
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⊡ Inguinal Hernia Clinical Case An inguinal hernia is a protrusion of abdominal cavity contents through the inguinal canal. They are very common. Inguinal hernia can be direct and indirect. Direct inguinal hernias occur medial to the inferior epigastric vessels when abdominal contents herniate through the superficial inguinal ring. Indirect inguinal hernias occur when abdominal contents protrude through the deep inguinal ring, lateral to the inferior epigastric vessels; this may be caused by failure of embryonic closure of the processus vaginalis. In the case of the female, the opening of the superficial inguinal ring is smaller than that of the male. As a result, the possibility for hernias through the inguinal canal in males is much greater because they have a larger opening.
A 39-year-old male patient was referred for an FDG PET/CT scan (Fig. 94.1) during the follow-up of subdiaphragmatic NHL. The scan demonstrated an area of increased tracer uptake in the left inguinal region. This was related to left inguinal hernia.
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Case 95 Clinical Diagnosis: Frontal Hematoma
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b
c
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⊡ Fig. 95.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) demonstrated an area of decreased tracer uptake in the right frontal
lobe. This was related to inveterate frontal hematoma (white arrows on b and c)
Case 95 Clinical Diagnosis: Frontal Hematoma
5
⊡ Frontal Hematoma Clinical Case A subdural hematoma, also known as a subdural hemorrhage (SDH), is a form of traumatic brain injury. Blood gathers within the outermost meningeal layer, between the dura mater, which adheres to the skull, and the arachnoid mater, which envelops the brain. Usually resulting from tears in bridging veins that cross the subdural space, subdural hemorrhages may cause an increase in intracranial pressure (ICP), which can cause compression of and damage to delicate brain tissue. Subdural hematomas are often life threatening when acute. Chronic subdural hematomas, however, have better prognoses if properly managed. In contrast, epidural hematomas are usually caused by tears in arteries, resulting in a buildup of blood between the dura mater and skull.
A 75-year-old male patient was referred for an FDG PET/CT scan (Fig. 95.1) during the follow-up of colon cancer. The scan demonstrated an area of decreased tracer uptake in the right frontal lobe, consistent with outcomes of hematoma.
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Case 96 Clinical Diagnosis: Chronic Atrial Fibrillation
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b
c
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⊡ Fig. 96.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) demonstrated mild increased tracer uptake in the spleen (red arrow) and
increased tracer uptake in the a trial walls (black and white arrows)
Case 96 Clinical Diagnosis: Chronic Atrial Fibrillation
5
⊡ Atrial Fibrillation Clinical Case Atrial fibrillation (AF or A-fib) is the most common cardiac arrhythmia (abnormal heart rhythm) and involves the two upper chambers (atria) of the heart. Its name comes from the fibrillating of the heart muscles of the atria instead of a coordinated contraction. Some people are asymptomatic despite having frequent episodes, while others experience symptoms that are troubling or incapacitating. While AF is not in itself generally considered immediately life threatening, it may result in palpitations, fainting, chest pain, or congestive heart failure. People with AF usually have a significantly increased risk of stroke (up to seven times that of the general population). Stroke risk increases during AF because blood may pool and form clots in the poorly contracting atria and especially in the left atrial appendage (LAA). The level of increased risk of stroke depends on the number of additional risk factors. If a person with AF has none, the risk of stroke is similar to that of the general population. However, many people with AF do have additional risk factors, and AF is a leading cause of stroke.
A 57-year-old male patient was referred for an FDG PET/CT scan (Fig. 96.1) for severe splenomegaly probably related to lymphoma. The scan demonstrated a moderate increased uptake in the spleen and increased uptake in the atrial walls. This was consistent with chronic atrial fibrillation.
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Case 97 Clinical Diagnosis: Large Uterine Fibromas
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b
c
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⊡ Fig. 97.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) demonstrated a large area of moderate increased tracer uptake in the uterus (black arrow on a and white arrows on b and c)
Case 97 Clinical Diagnosis: Large Uterine Fibromas
5
⊡ Uterine Fibromas Clinical Case Uterine fibroma is a benign encapsulated uterine tumor. It affects about 20% of women over the age of 30. The tumor may develop in the wall of the uterus or be attached to a stalk of tissue originating in the wall. Symptoms may include menstrual disorders such as menorrhagia. Symptoms are also likely to be related to the location of the tumor with respect to neighboring organs, as when a uterine fibroma causes pressure on the urinary bladder, producing symptoms of dysuria. Uterine fibromas rarely spread or become life threatening.
A 37-year-old male patient was referred for an FDG PET/CT scan (Fig. 97.1) during the follow-up of breast cancer. The scan was negative for malignancy relapse, but demonstrated moderate increased tracer uptake in the uterus. This was consistent with benign fibromas.
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Case 98 Clinical Diagnosis: Respiratory Failure
a
b
⊡ Fig. 98.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) demonstrated symmetrical increased tracer uptake in respiratory muscles
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c
because of postsurgical respiratory failure (white arrows on c)
Case 98 Clinical Diagnosis: Respiratory Failure
5
⊡ Respiratory Failure Clinical Case The term respiratory failure in medicine is used to describe inadequate gas exchange by the respiratory system, with the result that arterial oxygen and/or carbon dioxide levels cannot be maintained within their normal ranges. The main causes are pulmonary dysfunction, cardiac dysfunction, metabolic acidosis, drugs that suppress respiration, and neurological diseases.
A 53-year-old male patient underwent cardiac surgery. Because of the persistence of fever, he was referred for an FDG PET/CT scan (Fig. 98.1) that was negative for infection, and symmetrical increased tracer uptake was noticed in respiratory muscles because of postsurgical respiratory failure.
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Case 99 Clinical Diagnosis: Recent Bone Fracture
a
b
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⊡ Fig. 99.1 FDG PET/CT (a: MIP; b: coronal view of CT, PET, and fused images) demonstrated increased uptake in the left femur corresponding at CT image to displaced femoral fracture
Case 99 Clinical Diagnosis: Recent Bone Fracture
5
⊡ Femoral Fracture Clinical Case The femur is the largest and strongest bone, and has a good blood supply. Because of this and its protective surrounding muscle, the shaft requires a large amount of force to fracture. Once a fracture does occur, this same protective musculature usually is the cause of displacement, which commonly occurs with femoral shaft fractures. Neurovascular complications and pain management are the most significant issues in patients who come to the ED. The rich blood supply, when disrupted, can result in significant bleeding. Open fractures have added potential for infection.
A 43-year-old male patient was referred for an FDG PET/CT scan (Fig. 99.1) during the follow-up for HD. The scan demonstrated increased tracer uptake in the left femur, corresponding to displaced femoral fracture at CT.
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Case 100 Clinical Diagnosis: Bone Infarct
a
b
c
⊡ Fig. 100.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) demonstrated increased uptake in the right tibia. This was consistent with bone infarct (white arrow)
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Case 100 Clinical Diagnosis: Bone Infarct
5
⊡ Bone Infarct Clinical Case Bone infarct is a term used to refer to osteonecrosis within the metaphysis or diaphysis of a bone. A medullary infarct is a fairly equivalent term to bone infarct, but is less frequently used. The term may also be applied to some cases involving the epiphysis, but should not be used to describe subchondral osteonecrosis, when avascular necrosis is preferred. General causes of osteonecrosis include: trauma, Caisson disease, hemoglobinopathies, radiotherapy, connective tissue disorders, renal transplantation, corticosteroid excess (both endogenous and exogenous), pancreatitis, gout, Gaucher’s disease, and alcohol.
A 42-year-old female patient was referred for an FDG PET/CT scan (Fig. 100.1) during the follow-up for breast cancer. The scan was negative for malignancy, but demonstrated increased tracer uptake in the distal right tibia. This was interpreted as bone infarct. She was taking corticosteroids for a connectivitis.
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Case 101 Clinical Diagnosis: Pulmonary Infarction
a
b
c
⊡ Fig. 101.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) demonstrated increased uptake in the right lung. This was consistent with pulmonary infarct (white arrows on b and c)
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Case 101 Clinical Diagnosis: Pulmonary Infarction
5
⊡ Pulmonary Infarction Clinical Case Since the lung can obtain its oxygen from the alveolar gas and has a second blood supply through the bronchial arteries, occlusion of a pulmonary artery does not usually produce tissue necrosis. Because of the dual blood supply and free anastomosis between the pulmonary capillaries, small emboli do not cause any infarction in a healthy lung. Tissue distal to the obstructed artery may be normal or merely show congestion, hemorrhage, and intra-alveolar fibrin with intact alveolar walls. However, in spite of the dual blood supply from bronchial and pulmonary vessels, pulmonary infarction is very common. An embolus arising in any part of systemic circulation has to pass through the lungs. Infarction is common when the circulation of the lung is slowed down, associated with increased pulmonary circulatory pressure. Under such conditions, when a branch of pulmonary artery is blocked , the force of the bronchial arteries is insufficient to supply the obstructed area because of increased pulmonary circulatory pressure. Blood drains into the area from all the connections and stagnates there. Vessels in the alveolar walls give way, blood escapes into the alveolar space, and the whole area becomes dead and coagulated into a firm, blood-filled, solid, airless mass (hemorrhagic infarct). A big embolus blocking a big branch of the pulmonary artery causes sudden death from shock, without infarction.
An 81-year-old male patient was referred for an FDG PET/CT scan (Fig. 101.1) during the follow-up for gastric cancer. The scan was negative for malignancy, but demonstrated increased tracer uptake in the right lung. This was interpreted as pulmonary infarction.
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Cases 102–103 Clinical Diagnosis: Aortic Graft Infection
a
b
c
d
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⊡ Fig. 102.1 FDG PET/CT (a: MIP; b: coronal view of CT scan; c: PET; d: fused images) demonstrated increased uptake in the abdominal
aortic graft (black arrow on PET and white arrows onfused images). This was consistent with infection
Cases 102–103 Clinical Diagnosis: Aortic Graft Infection
5
⊡ Aortic Graft Infection Clinical Case 102 In recent years, prosthetic grafting has become a common method of repairing abdominal aortic aneurysms and bypassing atherosclerotic lesions. Elective abdominal aortic grafting is associated with low morbidity and mortality; however, several complications may occur. One of the most serious is aortic graft infection, which often requires removal of the graft after reconstruction of an alternate route of vascularization to the lower limbs. Clinically, the diagnosis of aortic graft infection is difficult because patients may have a variety of nondescript clinical complaints. Furthermore, even when the diagnosis is suspected, evaluation of the true extent of the graft infection is arduous. Indiumlabeled white blood cell scans (in-WBC) and computed tomography (CT) have each been reported as useful in the determination of the presence and extent of aortic graft infection.
An 82-year-old male patient was referred for an FDG PET/CT scan (Fig. 102.1) for characterizing a single pulmonary nodule. The scan was negative for malignancy, but demonstrated increased tracer uptake in the abdominal aorta, corresponding to a vascular graft. This was interpreted as infection.
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Cases 102–103 Clinical Diagnosis: Aortic Graft Infection
a
b
c
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⊡ Fig. 103.1 FDG PET/CT (a: MIP; b: CT; c: fused images) demonstrated increased uptake in the thoracic aortic graft (white arrows on b and c). This was consistent with infection
Cases 102–103 Clinical Diagnosis: Aortic Graft Infection
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Clinical Case 103 An 82-year-old male patient was referred for an FDG PET/CT scan (Fig. 103.1) during the follow-up of colon cancer. The scan was negative for malignancy, but demonstrated increased tracer uptake in the thoracic aorta, corresponding to a vascular graft. This was interpreted as infection.
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Case 104 Clinical Diagnosis: Hip Prosthesis Infection
a
b
216
c
⊡ Fig. 104.1 FDG PET/CT (a: MIP; b: CT, c: fused images) demonstrated increased uptake in the left hip acetabulum. This was consistent with infection (white arrows on b and c)
Case 104 Clinical Diagnosis: Hip Prosthesis Infection
⊡ Postsurgical Bone Infection
5
Clinical Case
See Cases 36, 37, 38. A 54-year-old female patient was referred for an FDG PET/CT scan (Fig. 104.1) for staging an NHL. She had a left hip prosthesis. She presented with mild left hip pain. The scan was positive for lymphoma in the mediastinum, and an area of increased tracer uptake was detected in the acetabulum of the left hip prosthesis. This was consistent with infection.
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Case 105 Clinical Diagnosis: Intraductal Papillary Mucinous Neoplasm (IPMN)
a
b
c
⊡ Fig. 105.1 FDG PET/CT (a: MIP; b: CT; c: fused images) demonstrated decreased uptake in the pancreatic head consistent with IPMN (white arrows on b and c)
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Case 105 Clinical Diagnosis: Intraductal Papillary Mucinous Neoplasm (IPMN)
⊡ Intraductal Papillary Mucinous Neoplasm Intraductal papillary mucinous neoplasm (IPMN) is a type of tumor (neoplasm) that grows within the pancreatic ducts (intraductal) and is characterized by the production of thick fluid by the tumor cells (mucinous). Intraductal papillary mucinous neoplasms are important because if they are left untreated some of them progress to invasive cancer (transform from a benign to a malignant tumor). Just as colon polyps can develop into colon cancer if left untreated, so too some intraductal papillary mucinous neoplasms progress into an invasive pancreatic cancer. Intraductal papillary mucinous neoplasms therefore represent an opportunity to treat a pancreatic tumor before it develops into an aggressive, hard-to-treat cancer.
5
Clinical Case A 78-year-old female patient was operated on 15 years before for basal-cell carcinoma. Recently, a disease relapse was diagnosed, and she underwent radiotherapy. After therapy, the patient was referred for an FDG PET/CT scan that detected a second disease relapse involving the left hemithorax (Fig. 105.1). Furthermore, a cold area was detected in the pancreatic head, corresponding to decreased density at CT. This was consistent with IPMN.
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Case 106 Clinical Diagnosis: Aortic Graft Leakage
a
b
c
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⊡ Fig. 106.1 FDG PET/CT (a: MIP; b: CT; c: fused images) demonstrated increased tracer concentration in the posterior mediastinum related to FDG leakage (white arrows on b and c)
Case 106 Clinical Diagnosis: Aortic Graft Leakage
5
⊡ Aortic Graft Leakage Clinical Case Leakage is a complication of vascular graft. Usually the diagnosis is based on contrast CT images.
A 78-year-old male patient was affected by a gastrointestinal stromal tumor and was referred for an FDG PET/CT scan for assessing the response to therapy with Gleevec (Fig. 106.1). The scan showed a complete metabolic response, but detected an area of increased concentration of FDG in the posterior mediastinum, close to the aortic graft. This area had not been present in the staging PET scan performed 2 weeks before. This finding was correlated to leakage of the aortic graft.
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Case 107 Clinical Diagnosis: Mastoiditis
a
b
222
⊡ Fig. 107.1 FDG PET/CT (a: MIP; b: three plain cuts of fused images) demonstrated increased tracer uptake in the left mastoid, consistent with inflammatory process (white arrows)
Case 107 Clinical Diagnosis: Mastoiditis
5
⊡ Mastoiditis Clinical Case Mastoiditis is an infection of the mastoid process, the portion of the temporal bone of the skull that is behind the ear and contains open, air-containing spaces. It is usually caused by untreated acute otitis media (middle ear infection) and used to be a leading cause of child mortality. With the development of antibiotics, however, mastoiditis has become quite rare in developed countries. It is treated with medications and/or surgery. If untreated, the infection can spread to surrounding structures, including the brain, causing serious complications
A 41-year-old male patient was treated for seminoma and was referred for an FDG PET/CT scan (Fig. 107.1). The scan was negative for malignancy, but showed increased uptake in the left mastoid consistent with an early inflammatory process.
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Case 108 Clinical Diagnosis: Pulmonary Microembolism
a
b
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⊡ Fig. 108.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) demonstrated small areas of mild increased tracer uptake peripherally in both
c
lungs. This was consistent with microembolism (white arrows on b and c)
Case 108
Clinical Diagnosis: Pulmonary Microembolism
5
⊡ Pulmonary Microembolism Clinical Case Shock results in peripheral vasoconstriction and diminished blood flow in the extremities. A stasis of blood on the venous side of the capillary bed results and leads to intravascular coagulation. When shock is corrected and the limbs are again perfused, the microemboli that have formed on the venous side are flushed into the lung, where they collect in the pulmonary arterioles and capillaries. If embolization is sufficient, it interferes profoundly with the CO2-O2 exchange function of the lung.
A 41-year-old male patient was treated for laryngeal cancer and was referred for an FDG PET/CT scan (Fig. 108.1). The scan was negative for malignancy, but showed several small areas of increased tracer uptake peripherally in both lungs. This was consistent to microembolism, which was subsequently confirmed at the diagnostic CT scan.
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Case 109 Clinical Diagnosis: Avascular Necrosis of the Head of the Humerus
a
b
⊡ Fig. 109.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) demonstrated increased tracer uptake in the left rotator cuff (yellow arrow). This was consistent with scapulo-humeral 226
c
periarthritis. At the corresponding CT images an area of decreased density was detected in the neck of the left humerus, which was cold at FDG (white arrow)
Case 109
Clinical Diagnosis: Avascular Necrosis of the Head of the Humerus
⊡ Avascular Necrosis of Bones
5
Clinical Case
See Case 43. A 38-year-old male patient had undergone bowel transplantation and was receiving treatment with steroids. He was referred for an FDG PET/CT scan (Fig. 109.1) during the follow-up of lymphoma. The scan was negative for malignancy, but increased tracer uptake in the left rotator cuff was detected. This was consistent with scapulo-humeral periarthritis. At the corresponding CT images, an area of decreased density was detected in the neck of the left humerus, which was cold at FDG. This was consistent with inveterate avascular necrosis due to prolonged use of corticosteroids.
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Cases 110–111 Clinical Diagnosis: Nonspecific Interstitial Pneumonia (NSIP)
a
b
⊡ Fig. 110.1 FDG PET/CT (a: MIP; b: CT scan; c: 228
fused images) demonstrated increased tracer uptake in both lungs. This was consistent with
c
nonspecific interstitial pneumonia related to chemotherapy
Cases 110–111 Clinical Diagnosis: Nonspecific Interstitial Pneumonia (NSIP)
⊡ Nonspecific Interstitial Pneumonia (NSIP) Nonspecific interstitial pneumonia (NSIP) has been proposed as a histological subtype of idiopathic interstitial pneumonia with lung biopsy findings that are inconsistent with those of other idiopathic interstitial pneumonias. NSIP has a broad spectrum of histologic findings and a variable prognosis. This is the second most common pattern of the lung injury seen in idiopathic pulmonary fibrosis (cryptogenic fibrosing alveolitis). Histologically, the most important feature is the diffuse and temporally uniform pattern of lung injury with variable degrees of inflammation and fibrosis. The changes can be divided into three categories: (1) predominantly inflammatory; (2) mixed inflammatory and fibrotic; (3) predominantly fibrotic. The predominantly inflammatory cases may resemble extrinsic allergic alveolitis, and the mixed inflammatory and fibrotic cases may be confused with usual interstitial pneumonia. Occasional fibroblast foci are seen in some cases, and areas of bronchiolitis obliterans organizing pneumonia (BOOP) are present in a number of cases. It is important to recognize NSIP as a distinct pattern of lung injury and to differentiate it from usual interstitial pneumonitis (UIP) since the progress of NSIP cases is much better than that of UIP. It is differentiated from usual interstitial pneumonitis by the temporal uniformity of the lesions, a prominent inflammatory interstitial infiltration, and the absence of honeycombing.
5
Clinical Case 110 A 45-year-old male patient was referred for an FDG PET/CT scan (Fig. 110.1) after chemotherapy for lymphoma. The scan was negative for malignancy, but increased tracer uptake in both the lungs was detected. This was consistent with nonspecific interstitial pneumonia related to chemotherapy.
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Cases 110–111 Clinical Diagnosis: Nonspecific Interstitial Pneumonia (NSIP)
a
b
230
⊡ Fig. 111.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) demonstrated increased tracer uptake in both lungs (white arrows on b and c).
c
This was consistent with nonspecific interstitial pneumonia related to smoking
Cases 110–111 Clinical Diagnosis: Nonspecific Interstitial Pneumonia (NSIP)
5
Clinical Case 111 A 72-year-old male patient who smoked was referred for an FDG PET/CT scan (Fig. 111.1) during the follow-up for colon cancer. The scan was negative for malignancy, but increased tracer uptake in both lungs was detected. This was consistent with nonspecific interstitial pneumonia related to smoking.
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Case 112 Clinical Diagnosis: Muscular Uptake
a
b
⊡ Fig. 112.1 FDG PET/CT (a: MIP; b: CT scan; 232
c: fused images) demonstrated several lymphomatous adenopathies in the mediastinum and bilateral axilla. Increased tracer uptake was
c
also noticed in the abdominal wall (black arrows on a and white arrows on b and c). This was related to persistent cough during the tracer uptake time
Case 112 Clinical Diagnosis: Muscular Uptake
5
Clinical Case A 79-year-old male patient was referred for an FDG PET/CT scan (Fig. 112.1) to stage NHL lymphoma. The scan detected several lymphomatous adenopathies in the mediastinum and bilateral axilla. Increased tracer uptake was also noticed in the abdominal wall. This was related to persistent cough during the tracer uptake time.
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Case 113 Clinical Diagnosis: Muscular Lipoma
a
b
c
234
⊡ Fig. 113.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) demonstrated an area of mild increased tracer uptake in the muscular compartment of the root of the left lower limb
(black arrow on a and white arrows on b and c). This corresponded to decreased density at CT scan and was consistent with muscular lipoma
Case 113 Clinical Diagnosis: Muscular Lipoma
5
⊡ Muscular Lipoma Clinical Case Lipomas are the most common soft-tissue tumor. These slow-growing, benign fatty tumors form soft, lobulated masses enclosed by a thin, fibrous capsule. Although it has been hypothesized that lipomas may rarely undergo sarcomatous change, this event has never been convincingly documented. It is more probable that lipomas are at the benign end of the spectrum of tumors, which, at the malignant end, include liposarcomas.
A 41-year-old male patient was referred for an FDG PET/CT scan (Fig. 113.1) during the follow-up of seminoma for rising alpha-fetoprotein. The scan was negative for malignancy, but an area of mild increased tracer uptake in the muscular compartment of the root of the left lower limb was detected. This corresponded to decreased density at CT scan and was consistent with muscular lipoma.
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Case 114 Clinical Diagnosis: Constrictive Pericarditis
a
b
c
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⊡ Fig. 114.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) demonstrated an area of mild increased tracer in the pericardium (black arrow on a and white arrows on b and c)
Case 114 Clinical Diagnosis: Constrictive Pericarditis
5
⊡ Constrictive Pericarditis Clinical Case Constrictive pericarditis occurs when a thickened fibrotic pericardium, of whatever cause, impedes normal diastolic filling. This usually involves the parietal pericardium, although it can involve the visceral pericardium. Acute and subacute forms of pericarditis (which may or may not be symptomatic) may deposit fibrin, which may, in turn, evoke a pericardial effusion. This often leads to pericardial organization, chronic fibrotic scarring, calcification, and restricted cardiac filling. The classic diagnostic conundrum of constrictive pericarditis is the difficulty in distinguishing it from restrictive cardiomyopathy (see Cardiomyopathy, restrictive) and other syndromes associated with elevated right-sided pressures that all share similar symptoms, physical findings, and hemodynamics. Although obtaining a careful history and performing a physical examination remain the cornerstones of evaluation, technologic advances have facilitated the diagnosis, particularly with the appropriate use of Doppler echocardiography, high-resolution computed tomography (CT), magnetic resonance imaging (MRI), and invasive hemodynamic measurement.
A 34-year-old male patient was referred for an FDG PET/CT scan (Fig. 114.1) during the follow-up of lymphoma. The scan was negative for malignancy, but an area of mild increased tracer uptake in the pericardium that was thickened at CT. This was consistent with pericarditis, and subsequently constrictive pericarditis was proved.
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Case 115 Clinical Diagnosis: Benign Asbestos Pleural Disease
a
b
⊡ Fig. 115.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) demonstrated a right laterocervical lymphomatous adenopathy (black arrow). Calcified bilateral nonhypermetabolic pleural
238
c
thickening is present (white arrow). This was consistent with benign asbestos pleural disease
Case 115 Clinical Diagnosis: Benign Asbestos Pleural Disease
5
⊡ Benign Asbestos Pleural Disease Clinical Case Circumscribed pleural plaques are the most common manifestation of asbestos exposure and comprise discrete areas of white or yellow thickening on the parietal pleura. They are frequently bilateral and symmetric, and occur particularly on the posterolateral chest wall between the fifth and eighth ribs, over the mediastinal pleura, and on the dome of the diaphragm. Histologic examination shows plaques to be acellular, with a “basket-weave” pattern of hyalinized collagen strands. They are covered by a single layer of normal mesothelial cells on the pleural surface. Pleural plaques typically develop 20–30 years after exposure, and their incidence increases with longer duration of exposure. They are found in as many as 50% of asbestos-exposed workers, but may also occur after low-dose exposures. The total surface area of pleural plaques measured via CT does not appear to be related to cumulative asbestos exposure.
A 68-year-old male patient was referred for an FDG PET/CT scan (Fig. 115.1) to stage a laterocervical NHL. The scan demonstrated a right laterocervical lymphomatous adenopathy. Calcified bilateral nonhypermetabolic pleural thickening was noticed. This was consistent with benign asbestos pleural disease.
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Case 116 Clinical Diagnosis: Pleuropericarditis in Inflammatory Bowel Disease (IBD)
a
b
240
⊡ Fig. 116.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) showed increased tracer uptake in the pleura and pericardium (white arrows on
c
b and c). This was consistent with pleuropericarditis
Case 116 Clinical Diagnosis: Pleuropericarditis in Inflammatory Bowel Disease (IBD)
⊡ Pleuropericarditis in Inflammatory Bowel Disease Inflammatory bowel disease (IBD) can affect the lung parenchyma and airways. Rarely it involves the pleural space and pericardium, causing inflammatory exudative pleural and/or pericardial effusions. Thoracic serositis in patients with IBD can cause pleuritis, pericarditis, pleuropericarditis, or myopericarditis. This is a relatively rare presentation of the uncommon and probably underreported and underrecognized pulmonary extraintestinal manifestations of IBD. Pleuropericardial inflammatory disease and effusion can be directly related to IBD, its complications, associated infections, or the medications used to treat it. Serositis directly related to IBD is a diagnosis of exclusion. It is important to evaluate the pleural effusion and rule out other etiologies before making this diagnosis. Pleural or pericardial biopsies are rarely necessary, and probably show nonspecific acute and chronic inflammatory changes. Although the specific pathophysiology of pleuropericardial disease in patients with IBD remains unclear, the response to systemic steroids is usually adequate.
5
Clinical Case A 32-year-old female patient was referred for an FDG PET/CT scan (Fig. 116.1) because of a suspicion of abdominal lymphoma since the CT scan had showed large abdominal adenopathies. She was affected by IBD. The scan was negative for malignancy but showed increased tracer uptake in the pleura and pericardium. This was consistent with pleuropericarditis, which had been diagnosed before PET.
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Case 117 Clinical Diagnosis: Bacterial Pneumonia
a
b
⊡ Fig. 117.1 FDG PET/CT (a: MIP; b: CT scan; 242
c: fused images) demonstrated focal increased uptake in the head and neck consistent with malignancy (red arrow). Furthermore, an area of severely increased tracer uptake was detected
c
in the middle lobe of the right lung (black and white arrows). Another area of increased uptake was detected in a homolateral hilar lymph node
Case 117 Clinical Diagnosis: Bacterial Pneumonia
5
⊡ Bacterial Pneumonia Clinical Case Pneumonia can be defined as inflammation of the lung parenchyma, in which consolidation of the affected part and a filling of the alveolar air spaces with exudate, inflammatory cells, and fibrin is characteristic. Infection by bacteria or viruses is the most common cause, although inhalation of chemicals, trauma to the chest wall, or infection by other infectious agents such as rickettsia, fungi, and yeasts may occur. Bacterial pneumonia is caused by a pathogenic infection of the lungs and may present as a primary disease process or as the final coup de grâce in the individual who is already debilitated. Anatomic or radiological distribution of pneumonia includes lobar (known as focal or nonsegmental pneumonia), multifocal/lobular, and interstitial (focal diffuse).
A 56-year-old male patient was referred for an FDG PET/CT scan (Fig. 117.1) because of a suspicion of head and neck cancer. The scan was positive for malignancy. Furthermore, an area of severely increased tracer uptake was detected in the middle lobe of the right lung. Another area of increased uptake was detected in a homolateral hilar lymph node. This was consistent with bacterial pneumonitis.
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5
Case 118 Clinical Diagnosis: Postradiotherapy Changes
a
b
⊡ Fig. 118.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) demonstrated local relapse and supradiaphragmatic metastasis (red arrows). Furthermore, a mild increase in tracer uptake 244
c
was detected in the sacrum. At corresponding CT images, alterations in bone density were present (white arrows)
Case 118 Clinical Diagnosis: Postradiotherapy Changes
5
⊡ Postradiotherapy Changes Clinical Case It is recognized that the incidental radiotherapy of bone increases the risk for pathological fracture, and that this risk is related to both the radiation dose and volume. This risk for fracture is generally presumed to result from a radiotherapy-induced decrease in bone density. However, alterations in bone density subsequent to RT have not been well quantified.
A 55-year-old female patient had been treated for uterine cancer with surgery, radiotherapy, and chemotherapy. She was referred for an FDG PET/CT scan (Fig. 118.1) for suspected uterine cancer relapse. The scan was positive for local malignancy. Supradiaphragmatic metastases were detected. Furthermore, a mild increase in tracer uptake was detected in the sacrum. At corresponding CT images, alterations in bone density were present. This was consistent with postradiotherapy changes.
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Case 119 Clinical Diagnosis: Xanthogranulomatous Lymphadenitis
a
b
246
c
⊡ Fig. 119.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) demonstrated increased tracer uptake in the enlarged inguinal adenopathies (black arrow on a and white arrows on b and c)
Case 119
Clinical Diagnosis: Xanthogranulomatous Lymphadenitis
5
⊡ Xanthogranulomatous Lymphadenitis Clinical Case Xanthogranulomatous lymphadenitis is an unusual type of granulomatous lymphadenitis, which can be suspected of being a malignant lymphoma. Histologically, this lesion shows a striking xanthomatous appearance because of collections of foamy histiocytes interspersed with chronic inflammatory cells and resulting in a storage-like aspect. Evidence indicates that this process merely represents the reabsorption and healing phases of an acute suppurative lymphadenitis, with histopathological features comparable to those of xanthogranulomatous pyelonephritis.
A 31-year-old male patient was HIV positive and was referred for an FDG PET/ CT scan (Fig. 119.1) for suspected inguinal lymphoma. The scan was positive in the enlarged inguinal adenopathies. A biopsy was indicated, and the final diagnosis was xanthogranulomatous lymphadenitis.
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5
Case 120 Clinical Diagnosis: Knee Prosthesis: Physiological Biodistribution
a
b
c
248
⊡ Fig. 120.1 FDG PET/CT (a: MIP; b: coronal view of CT, PET; c: fused images) demonstrated increased tracer uptake surrounding a left knee prosthesis (black arrows)
Case 120 Clinical Diagnosis: Knee Prosthesis: Physiological Biodistribution
5
Clinical Case A 65-year-old female patient was referred for an FDG PET/CT scan (Fig. 120.1) for a suspected relapse of breast cancer. The scan was negative for malignancy relapse. However, increased uptake surrounding a left knee prosthesis was detected. This was consistent with physiological activity.
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5
Case 121 Clinical Diagnosis: Nodular Radiation Pneumonitis
a
b
⊡ Fig. 121.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) demonstrated mild increased tracer uptake in the right lung, corresponding 250
c
to an area of increased density (white arrows on b and c)
Case 121 Clinical Diagnosis: Nodular Radiation Pneumonitis
5
⊡ Nodular Radiation Pneumonitis Clinical Case Radiation-induced lung disease (RILD) due to radiation therapy is common. Radiological manifestations are usually confined to the lung tissue within the radiation port and are dependent on the interval after completion of treatment. In the acute phase, RILD typically manifests as ground-glass opacity or attenuation, or as consolidation; in the late phase, it typically manifests as traction bronchiectasis, volume loss, and scarring. Sometimes the radiation injury can present as a nodular area of increased attenuation.
A 62-year-old female patient was referred for an FDG PET/CT scan (Fig. 121.1) for suspected breast cancer relapse. She had undergone a right mastectomy 6 months before and been treated with radiation therapy. The scan was negative for malignancy relapse. However, an area of mild increased tracer uptake was detected in the right lung, corresponding to increased density at CT. The final diagnosis was nodular radiation pneumonitis.
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Case 122 Clinical Diagnosis: Spina Bifida
a
b
c
252
⊡ Fig. 122.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) demonstrated mild increased tracer uptake in the sacrum. The vertebral fora-
men was open at this level (white arrows on b and c)
Case 122 Clinical Diagnosis: Spina Bifida
5
⊡ Spina Bifida Clinical Case Spina bifida is a developmental congenital disorder caused by the incomplete closing of the embryonic neural tube. Some vertebrae overlying the spinal cord are not fully formed and remain unfused and open. If the opening is large enough, this allows a portion of the spinal cord to protrude through the opening in the bones. There may or may not be a fluid-filled sac surrounding the spinal cord. Other neural tube defects include anencephaly, a condition in which the portion of the neural tube that will become the cerebrum does not close, and encephalocele, which results when other parts of the brain remain unfused. Spina bifida malformations fall into four categories: spina bifida occulta, spina bifida cystica (myelomeningocele), meningocele, and lipomeningocele. The most common locations of the malformations are the lumbar and sacral areas.
A 29-year-old male patient was referred for an FDG PET/CT scan (Fig. 122.1) for suspected lymphoma. The scan was negative for malignancy. An area of mild increased uptake was detected in the sacrum. This was consistent with spina bifida. The patient also had a plastic urinary bladder.
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5
Case 123 Clinical Diagnosis: Spondylolisthesis
a
b
254
⊡ Fig. 123.1 FDG PET/CT (a: MIP; b: sagittal view of CT, PET, and fused images) demonstrated mild increased tracer uptake in L4-L5 (black arrow on a and white arrows on b)
Case 123
Clinical Diagnosis: Spondylolisthesis
5
⊡ Spondylolisthesis Clinical Case Spondylolisthesis involves the anterior or posterior displacement of a vertebra or the vertebral column in relation to the vertebrae below.
A 25-year-old male patient was referred for an FDG PET/CT scan (Fig. 123.1) to assess the lymphoma treatment response. The scan was negative for malignancy. An area of mild increased uptake was detected in the L4-L5 region. This was consistent with inflammation due to previously diagnosed spondylolisthesis.
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Case 124 Clinical Diagnosis: Rib Fracture
a
b
c
256
⊡ Fig. 124.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) demonstrated lymphoma relapse in the left inguinal area (red arrow) and
increased uptake in a left rib (white arrow), consistent with recent trauma
Case 124 Clinical Diagnosis: Rib Fracture
5
⊡ Rib Fracture Clinical Case A rib fracture is a break or fracture in one or more of the bones making up the rib cage. The middle ribs are the ones most commonly fractured. Fractures usually occur from direct blows or from indirect crushing injuries. The weakest part of a rib is just anterior to its angle, but a fracture can occur anywhere. The most commonly fractured ribs are the seventh and tenth.
A 61-year-old male patient was referred for an FDG PET/CT scan (Fig. 124.1) for a suspected relapse of follicular lymphoma. The scan was positive in the left inguinal area. Furthermore, an area of increased uptake was detected in a left rib. This was consistent with fracture due to a trauma while gardening.
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5
Case 125 Clinical Diagnosis: Inferior Vena Cava Thrombosis
a
b
c
258
⊡ Fig. 125.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) showed an area of increased uptake in the inferior vena cava associated with small bilateral areas of increased uptake in the lungs
Case 125 Clinical Diagnosis: Inferior Vena Cava Thrombosis
5
⊡ Inferior Vena Cava Thrombosis (IVCT) Clinical Case Thrombosis of the inferior vena cava (IVC) is an underrecognized entity with a variety of clinical presentations. To a large degree, the etiology of IVCT mirrors that of DVT in general. However, specific situations relate to the IVC only, but the wide variety of these situations all relate in one or more ways to Virchow’s classic description. The most frequent causes are: tumors, compression, hematoma/trauma, dysfunctional coagulation system, and iatrogenic. Patients may be asymptomatic or they may present only after complications occur.
A 54-year-old male patient was referred for an FDG PET/CT scan (Fig. 125.1) for a suspected relapse of lymphoma. The scan was negative for malignancy. An area of increased uptake was detected in the inferior vena cava associated with small bilateral areas of increased uptake in the lungs. This was subsequently diagnosed as inferior vena cava thrombosis with bilateral pulmonary embolism.
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5
Case 126 Clinical Diagnosis: Duodenal Ulcer
a
b
c
d
260
⊡ Fig. 126.1 FDG PET/CT (a, c: MIP; b, d: fused images) demonstrated an area of increased uptake in the spine (a, red arrow) that disappeared after the completion of therapy (c). Furthermore, a focal area
of increased uptake was detected in the duodenum (a, black arrow b, white arrow) that disappeared after appropriate anti-ulcer therapy (black cross on c and red cross on d)
Case 126 Clinical Diagnosis: Duodenal Ulcer
5
⊡ Duodenal Ulcer Clinical Case A peptic ulcer, also known as PUD or peptic ulcer disease, is the most common ulcer of an area of the gastrointestinal tract that is usually acidic. It is defined as mucosal erosions ³0.5 cm. As many as 70–90% of such ulcers are associated with Helicobacter pylori. Ulcers can also be caused or worsened by drugs such as aspirin, clopidogrel, ibuprofen, and other NSAIDs. Contrary to general belief, four times as many peptic ulcers arise in the duodenum than in the stomach itself. About 4% of stomach ulcers are caused by a malignant tumor, so multiple biopsies are needed to exclude cancer. Duodenal ulcers are generally benign.
A 45-year-old male patient was affected by spondylodiscitis and was referred for an FDG PET/CT scan (Fig. 126.1a, b) for evaluating the response to therapy. The scan was still positive for infection in the spine. Furthermore, an area of increased uptake was detected in the duodenum. This was consistent with an ulcer, probably due to a prolonged NSAIDs therapy. The patient continued the antibiotic therapy for discitis and was subsequently referred for a second FDG PET/CT. The scan was negative both in the spine and duodenum (Fig. 126.1c, d).
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Case 127 Clinical Diagnosis: Shingles
a
b
⊡ Fig. 127.1 FDG PET/CT (a: MIP; b: CT scan; c: fused images) demonstrated an area of increased uptake in the left laterocervical region
262
c
consistent with shingles (black arrow on a and white arrows on b and c)
Case 127 Clinical Diagnosis: Shingles
5
⊡ Shingles Clinical Case Shingles is a viral disease produced by the chicken pox virus. It is characterized by pain and a blistering rash that occurs along the nerves that have housed the dormant chicken pox virus since its last effects on an individual. Stress may lead to shingles. The disease starts with tingling, itchiness, or pain on an infected person’s skin. After a few days, the disease causes a blistering rash. This rash may be on the trunk or face. The rash grows into small blisters filled with fluid. These blisters dry out and crust over for several days. The worst period of the rash causes anything from mild itching to extreme pain. The rash is confined to one region of the body.
A 75-year-old male patient was affected by lymphoma and was referred for an FDG PET/CT scan (Fig. 127.1) for evaluating the response to therapy. The scan was negative for malignancy, but an area of diffuse increased tracer uptake was present in the neck. This was consistent with shingles, which was also clinically evident.
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FDG: Rare Findings
Suggested Reading Abu-Hijleh M, Evans S, Aswad B (2010) Pleuropericarditis in a patient with inflammatory bowel disease: a case presentation and review of the literature. Lung 188:505–510 Cadili A, de Gara C (2008) Complications of splenectomy. Am J Med 121:371–375 Choi YW, Munden RF, Erasmus JJ, Park KJ, Chung WK, Jeon SC, Park C-K (2004a) Effects of radiation therapy on the lung: radiologic appearances and differential diagnosis. Radiographics 24:985–998 Choi YW, Munden RF, Erasmus JJ, Park KJ, Chung WK, Jeon SC, Park C-K (2004b) Effects of radiation therapy on the lung: radiologic appearances and differential diagnosis. Radiographics 24:985–998 Cook RJ, Ashton RW, Aughenbaugh GL, Ryu JH (2005) Septic pulmonary embolism. Chest 128(1):162–166 Cozzutto C, Soave F (1979) Xanthogranulomatous lymphadenitis. Virchows Arch 385(1):103–108 Cullen DJ, Hawkey GM, Greenwood DC et al (1997) Peptic ulcer bleeding in the elderly: relative roles of Helicobacter pylori and non-steroidal anti-inflammatory drugs. Gut 41(4):459–462 Eble JN (1998a) Angiomyolipoma of kidney. Semin Diagn Pathol 15(1):21–40 Eble JN (1998b) Angiomyolipoma of kidney. Semin Diagn Pathol 15(1):21–40 Fellrath JM, du Bois RM (2003) Idiopathic pulmonary fibrosis/cryptogenic fibrosing alveolitis. Clin Exp Med 3(2):65–83
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Hellmann DB, Grand DJ, Freischlag JA (2007) Inflammatory abdominal aortic aneurysm. JAMA 297(4):395–400 Izzo L, Boschetto A, Brachini G et al (2001) “Strawberry” gallbladder: review of the literature and our experience. G Chir 22(1–2):33–36 Karhunen PJ (1986) Benign hepatic tumours and tumour like conditions in men. J Clin Pathol 39(2):183–188 Lorente L, Henry C, Martín MM, Jiménez A, Mora ML (2005) Central venous catheter-related infection in a prospective and observational study of 2,595 catheters. Crit Care 9(6):R631–R635 Mark AS, McCarthy SM, Moss AA, Price D (1985) Detection of abdominal aortic graft infection: comparison of CT and In-labeled white blood cell scans. AJR Am J Roentgenol 144:315–318 Nakatomi H, Kin T, Saito N (2011) Surgical management of brainstem cavernous angioma. Brain Nerve 63(1):31–40 Rudd RM (1996) New developments in asbestos-related pleural diseases. Thorax 51:210–216 Shea JA, Berlin JA, Escarce JJ et al (1994) Revised estimates of diagnostic test sensitivity and specificity in suspected biliary tract disease. Arch Intern Med 154(22):2573–2581 Tsubamoto M, Müller NL, Johkoh T, Ichikado K, Taniguchi H, Kondoh Y, Fujimoto K, Arakawa H, Koyama M, Kozuka T, Inoue A, Sumikawa M, Murai S, Honda O, Tomiyama N, Hamada S, Nakamura H (2005) Pathologic subgroups of nonspecific interstitial pneumonia: differential diagnosis from other idiopathic interstitial pneumonias on high-resolution computed tomography. J Comput Assist Tomogr 29(6):793–800
Chapter 6
11C-Choline: Rare Findings
Case 128 Clinical Diagnosis: Vertebral Collapse . . . . . 266 Case 129 Clinical Diagnosis: Interstitial Pulmonary Edema . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 268 Case 130 Clinical Diagnosis: Bullous Emphysema and Pulmonary Fibrosis . . . . . . . . . . . . . . . . . . . 270 Case 131 Clinical Diagnosis: Inguinal Hernia . . . . . . . . 272 Case 132 Clinical Diagnosis: Rib Fractures . . . . . . . . . . 274 Case 133 Clinical Diagnosis: Implantable Cardiac Device Infection . . . . . . . . . . . . . . . . . . 276 Case 134 Clinical Diagnosis: Lymphoma . . . . . . . . . . . . 278 Case 135 Clinical Diagnosis: Trauma . . . . . . . . . . . . . . . . 280
C. Nanni, S. Fanti, PET-CT: Rare Findings and Diseases, DOI 10.1007/978-3-642-24699-9_6, © Springer-Verlag Berlin Heidelberg 2012
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Case 128 Clinical Diagnosis: Vertebral Collapse
a
b
266
⊡ Fig. 128.1 FDG PET/CT (a: MIP; b: sagittal view of CT, PET, and fused images) demonstrated an area of decreased uptake in L2,
corresponding to a vertebral collapse (white arrow)
Case 128 Clinical Diagnosis: Vertebral Collapse
6
⊡ Vertebral Collapse Clinical Case A vertebral collapse is the breakdown of a vertebra resulting in decreased height of its body. The collapse may occur to a variable extent, and in more severe cases it may be associated with an increased width of the body with possible bulging of the posterior wall towards the spinal canal and consequent spinal cord or nerve root compression. A vertebral breakdown is, of course, observed in traumatic contexts, but the term collapse usually applies more properly to spontaneous nontraumatic occurrences. In spontaneous collapse an underlying condition, such as a primary osseous disease or secondary replacement by tumors, is responsible for a weakening of the vertebral osseous structure. Spontaneous vertebral collapse may be clinically apparent and may be responsible for an overwhelming, acute, paralyzing back pain syndrome. The observation of a collapsed vertebral body as an incidental finding is not infrequent in clinical radiological practice.
A 78-year-old male patient was affected by prostate cancer and was referred for an 11C-choline PET/CT scan (Fig. 128.1) because of rising PSA levels and lower back pain. The scan was negative for malignancy, but a completely cold area was detected in L2, corresponding to a vertebral collapse at CT.
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Case 129 Clinical Diagnosis: Interstitial Pulmonary Edema
a
b
c
268
⊡ Fig. 129.1 FDG PET/CT (a: MIP; b: CT; c: fused images) demonstrated multiple small bone lesions (red arrows). Furthermore, increased
tracer uptake was detected in both lungs, consistent with interstitial pulmonary edema (black and white arrows)
Case 129 Clinical Diagnosis: Interstitial Pulmonary Edema
6
⊡ Interstitial Pulmonary Edema Clinical Case See Case 91. An 81-year-old male patient was affected by prostate cancer and was referred for an 11C-choline PET/CT scan (Fig. 129.1) because of rising PSA levels. He was affected by heart failure. The scan demonstrated multiple small bone lesions. Furthermore, increased tracer uptake was detected in both the lungs, consistent with interstitial pulmonary edema.
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Case 130 Clinical Diagnosis: Bullous Emphysema and Pulmonary Fibrosis
a
b
⊡ Fig. 130.1 FDG PET/CT (a: MIP; b: CT; c: fused images) demonstrated increased uptake in both lungs (black arrows on a and white arrows 270
c
on b and c). This corresponded, at CT images, to areas of bullous emphysema and pulmonary fibrosis
Case 130 Clinical Diagnosis: Bullous Emphysema and Pulmonary Fibrosis
6
⊡ Bullous Emphysema Clinical Case Bullous emphysema is histologically referred to as the presence of emphysematous areas with a complete destruction of lung tissue producing an air space greater than 1 cm in diameter. Bullae must be clearly differentiated from other disorders such as lung cysts (developmental anomalies; they are lined by respiratory epithelium) and blebs (small subpleural collections of air). Most of the outer surface of bullae is made of visceral pleura, whereas the inner layer consists of fibrous tissue formed mainly by the destroyed adjacent lung.
An 81-year-old male patient was affected by prostate cancer and was referred for an 11C-choline PET/CT scan (Fig. 130.1) because of rising PSA levels. The scan was negative for prostate cancer relapse, but mild increased uptake was present in both lungs. This corresponded, at CT images, to areas of bullous emphysema and pulmonary fibrosis.
⊡ Pulmonary Fibrosis Pulmonary fibrosis is the formation or development of excess fibrous connective tissue (fibrosis) in the lungs. It is also described as “scarring of the lung.” Pulmonary fibrosis involves a gradual exchange of normal lung parenchyma with fibrotic tissue. The replacement of normal lung with scar tissue causes an irreversible decrease in the oxygen diffusion capacity. In addition, decreased compliance makes pulmonary fibrosis a restrictive lung disease.
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Case 131 Clinical Diagnosis: Inguinal Hernia
a
b
c
⊡ Fig. 131.1 FDG PET/CT (a: MIP; b: CT; c: fused images) demonstrated increased uptake in the left inguinal region (black arrow on a and white arrow on b and c)
272
Case 131 Clinical Diagnosis: Inguinal Hernia
6
⊡ Inguinal Hernia Clinical Case See Case 94. A 65-year-old male patient was affected by prostate cancer and was referred for an 11C-choline PET/CT scan (Fig. 131.1) because of rising PSA levels. The scan was negative for prostate cancer relapse, but an area of increased tracer uptake was detected in the left inguinal region. This was subsequently proven to be inguinal hernia.
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Case 132 Clinical Diagnosis: Rib Fractures
a
b
c
⊡ Fig. 132.1 FDG PET/CT (a: MIP; b: CT; c: fused
increased uptake was present in the corresponding lung parenchyma (black arrow on a and white arrow on b and c)
images) demonstrated increased tracer uptake in a right rib posteriorly. A second area of
274
Case 132 Clinical Diagnosis: Rib Fractures
6
⊡ Rib Fractures Clinical Case See Case 124. A 61-year-old male patient was affected by prostate cancer and was referred for an 11C-choline PET/CT scan (Fig. 132.1) because of rising PSA levels. The scan was negative for prostate cancer relapse, but increased tracer uptake was present in a right rib posteriorly. A second area of increased uptake was present in the corresponding lung parenchyma. This was consistent with rib fracture and pulmonary hematoma.
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Case 133 Clinical Diagnosis: Implantable Cardiac Device Infection
a
b
⊡ Fig. 133.1 FDG PET/CT (a: MIP; b: CT; c: fused
276
images) detected prostate cancer relapse in an external iliac lymph node and in the sternum (red arrows). Furthermore, increased tracer
c
uptake was present in the pectoral pocket of an implantable cardiac device (ICD) (black and white arrows)
Case 133 Clinical Diagnosis: Implantable Cardiac Device Infection
⊡ Implantable Cardiac Device (ICD) Infection See Case 22.
6
Clinical Case A 72-year-old male patient was affected by prostate cancer and was referred for an 11C-choline PET/CT (Fig. 133.1) because of rising PSA levels. The scan detected prostate cancer relapse in an external iliac lymph node and in the sternum. Furthermore, increased tracer uptake was present in the pectoral pocket of an implantable cardiac device (ICD). This was subsequently proven to be infected.
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Case 134 Clinical Diagnosis: Lymphoma
a
b
c
⊡ Fig. 134.1 FDG PET/CT (a: MIP; b: CT; c: fused images) showed increased uptake in several left laterocervical lymph nodes (black arrow on a and white arrow on b and c)
278
Case 134 Clinical Diagnosis: Lymphoma
6
⊡ Lymphoma Clinical Case Non-Hodgkin’s lymphomas (NHLs) are a diverse group of blood cancers that include any kind of lymphoma except Hodgkin’s lymphomas. Types of NHL vary significantly in their severity, from indolent to very aggressive. The latest lymphoma classification, the 2008 WHO classification, has largely abandoned the “Hodgkin’s”vs. “non-Hodgkin’s”grouping. Instead, it lists over 70 different forms of lymphomas in four broad groups.
A 59-year-old male patient was affected by prostate cancer and was referred for an 11C-choline PET/CT scan (Fig. 134.1) because of rising PSA levels. The scan was negative for prostate cancer relapse, but increased uptake was present in several left laterocervical lymph nodes. A subsequent biopsy proved an NHL.
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Case 135 Clinical Diagnosis: Trauma
a
b
c
⊡ Fig. 135.1 FDG PET/CT (a: MIP; b: CT; c: fused images) showed diffused increased uptake in the sacrum (white arrows)
280
Case 135 Clinical Diagnosis: Trauma
6
Clinical Case A 59-year-old male patient was affected by prostate cancer and was referred for an 11C-choline PET/CT scan (Fig. 135.1) because of rising PSA levels. The scan was negative for prostate cancer relapse, but diffuse moderate increase in tracer uptake was present in the sacrum. This was consistent with a very recent sacral trauma.
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Chapter 7
68Ga-Somatostatine Analogs: Rare Findings
Case 136 Clinical Diagnosis: Multiple Myeloma . . . . . 284
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Case 136 Clinical Diagnosis: Multiple Myeloma
a
b
c
⊡ Fig. 136.1 FDG PET/CT (a: MIP; b: CT; c: fused images) showed diffuse increased uptake in the left sacroiliac joint (white arrows), ribs, lumbar spine and skull (black arrows) 284
Case 136 Clinical Diagnosis: Multiple Myeloma
7
⊡ Multiple Myeloma Clinical Case See Case 63. A 53-year-old male patient was referred for a 68Ga-DOTA NOC PET/CT scan (Fig. 136.1) for suspected Zollinger Ellison syndrome. The scan was negative, but increased uptake in the left sacroiliac joint, lumbar spine, ribs and skull was detected. These areas were subsequently proven to be related to multiple myeloma.
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Index
A Abscess, 24–29, 65, 99, 177, 193 Adenocarcinoma, 15, 138–139, 153 Alveolitis, 164–165, 229 Amyloidosis, 6–7 Aortic aneurysm, 49, 166–167, 213 Appendicitis, 108–109 Arthritis, 35, 50–51, 87, 93, 101 Asbestos, 9, 238–239 Aspergillosis, 12–13
Fibromas, 202–203 Fibrosarcoma, 104–105 Fibrosis, 9, 19, 52–53, 167, 185, 229, 270, 271 Fractures, 5, 71, 75, 129, 131, 206–207, 245, 256–257, 274–275
G Giant cell tumor (GCT), 4–5, 79 Graves-Basedow, 32–33
H B Basal-cell carcinoma (BCC), 30–31, 219 Brain hemorrhage, 140–141
Hematoma, 198–199, 259, 275 Hepatocellular carcinoma, 126–127 Hernia, 196–197, 272–273 Herniation, 54–55
C Castleman, 22–23 Cavernous hemangioma, 168–169, 171 Cholecystitis, 176–177, 179 Cholesterolosis, 178–179 Colitis, 180–181 Corpus luteum, 182–183 Cystic serous adenoma, 152–153
I
Discitis, 36–37, 76, 261 Double ureter, 188–189
IBD. See Inflammatory bowel disease (IBD) Infarct, 208–211 Infarction, 193, 210–211 Infection, 4, 5, 7, 13, 15, 17, 21, 27, 34, 35, 37, 41, 44–49, 57, 59, 66–69, 74–77, 82–83, 89, 110–111, 127, 133, 186–187, 191, 205, 207, 212–217, 223, 241, 243, 261, 276–277 Inflammatory bowel disease (IBD), 240–241 Intraductal papillary mucinous neoplasm (IPMN), 218–219
E
K
EBV, 110–111 Edema, 95, 190–191, 268–269 Embolism, 87, 192–193, 259 Emphysema, 15, 185, 194–195, 270–271 Epilepsy, 118–119 Erdheim-Chester, 38–39 Erysipelas, 34–35
Kidney stone, 174–175 Knee prosthesis, 34, 35, 248–249
D
F Failure, 27, 45, 133, 145, 185, 191, 197, 201, 204–205, 269 Fibrillation, 200–201
L Leakage, 220–221 Lipoma, 234–235 Liver hemangioma, 170–171 Lymphadenitis, 246–247 Lymphoma, 11–13, 16, 17, 21, 23, 43, 55, 57, 62–63, 102–103, 111, 146–147, 179, 201, 217, 227, 229, 233, 237, 241, 247, 253, 255–257, 259, 263, 278–279
C. Nanni, S. Fanti, PET-CT: Rare Findings and Diseases, DOI 10.1007/978-3-642-24699-9, © Springer-Verlag Berlin Heidelberg 2012
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Index
M MALT, 102–103 Mastoiditis, 222–223 Mesenteritis, 56–57 Mesothelioma, 60–61 Microcystic tumor, 116–117 Microembolism, 224–225 Multiple myeloma (MM), 7, 128–129, 191, 284–285 Muscular uptake, 232–233
N Necrosis, 15, 27, 41, 86–87, 106, 107, 209, 211, 226–227 Necrotizing fasciitis, 40–41 Neuroendocrine tumor, 155–157, 163 Nonspecific interstitial pneumonia (NSIP), 228–231
O Osteomyelitis, 58–59, 66–69, 87 Otitis, 88–89, 223
P Paget’s disease, 5, 70–73, 130–131 Pancreatitis, 154–155, 163, 209 Pericarditis, 236–237, 241 Pilonidal cyst, 64–65 Pneumonia, 16–17, 20–21, 191, 228–231, 242–243 Pneumonitis, 229, 243, 250–251 Polydermatomyositis, 92–93 Portal thrombosis, 162–163 Primary hyperparathyroidism, 144–145 Pulmonary heart, 184–185
Remitting seronegative symmetrical synovitis with pitting edema (RS3PE), 94–95 Renal angiomyolipoma, 172–173 Renal cell carcinoma (RCC), 134–135 Respiratory, 7, 83, 93, 133, 191, 193, 204–205, 271 RS3PE. See Remitting seronegative symmetrical synovitis with pitting edema (RS3PE)
S Sacroiliitis, 100–101 Sarcoidosis, 18–19, 90–91, 95, 132–133 Sarcoma, 71, 84–85, 106–107, 131, 148–149, 169 Scar cancer, 14–15 Shingles, 262–263 Spina bifida, 252–253 Spindle cell carcinoma, 120–121 Spondylolisthesis, 254–255 Synovitis, 51, 78–81
T TB. See Tuberculosis (TB) Thrombosis, 35, 87, 162–163, 187, 258–259 Trauma, 27, 35, 37, 57, 59, 87, 141, 199, 209, 243, 256, 257, 259, 267, 280–281 Tuberculosis (TB), 96–99
U Ulcer, 260–261
V Vaquez disease, 42–43 Vertebral collapse, 37, 266–267 Von Recklinghausen, 112–113
R Radiotherapy, 31, 63, 147, 149, 169, 209, 219, 244–245 RCC. See Renal cell carcinoma (RCC)
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W Wilms’ tumor, 114–115
