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Desmoplastic melanoma is a rare subtype of malignant melanoma, which is unusual in that it is more often associated with local recurrence than with lymph node or distant metastatic spread. The histologic architecture of this melanoma subtype differs from conventional melanoma in that the melanoma cells are interspersed within an abundant collagenous stroma. We present a case that demonstrates both true positive and false negative findings on F-18 FDG PET/CT imaging in a case of recurrent desmoplastic melanoma.

A 37-year-old woman with symptoms and laboratory investigations suggesting a diagnosis of paraganglioma had a 3-cm mass in the right atrioventricular groove on MRI. The mass had intense F-18 FDG uptake on F-18 FDG PET/CT. After surgery, histologic examination revealed a 16.5 g paraganglioma

A 71-year-old man with newly diagnosed malignant mesothelioma was referred for an F-18 FDG PET/CT study to evaluate the extent of disease. PET showed mild FDG uptake in the right chest, corresponding to a lobulated, mass-like right pleural effusion versus thickening involving the entire right pleural space, and some mediastinal involvement, on the accompanying CT scan. In addition, marked FDG uptake was seen in the proximal left humerus, suspicious for an osseous metastasis. The corresponding CT scan findings of cortical thickening and a "Swiss cheese" appearance were most consistent with Paget disease. The intense FDG uptake in an osseous lesion on FDG-PET in our case reminds us of the variable nature of FDG uptake in Paget disease, the possibility of false-positive findings on FDG-PET in patients with cancer, and the usefulness of the fusion techniques in the evaluation of skeletal lesions, with the potential for discriminating between benign Paget disease and other pathologic bone findings.

F-18 FDG PET/CT is used to evaluate head and neck malignancies, including salivary gland tumors. We describe the FDG PET/CT features of a submandibular gland oncocytoma. An 85-year-old patient with small cell cancer of the lung and a history of squamous cell carcinoma of the lower lip was evaluated with FDG PET/CT. There was an intensely hypermetabolic left submandibular gland lesion that was suspected for a metastasis. Ultrasound-guided fine needle aspirate of the lesion proved to be a submandibular gland oncocytoma.

To assess the feasibility and first experience of combined (18)F-FDG-PET)/dynamic contrast-enhanced (DCE) CT in evaluating breast cancer.Nine consecutive female patients (mean age 64.2 years, range 52-74 years) with primary breast carcinoma were prospectively recruited for combined (18)F-FDG PET/DCE-CT. Dynamic CT data were used to calculate a range of parameters of tumour vascularity, and tumour (18)F-FDG uptake (standardized uptake value, SUVmax) was used as a metabolic indicator.One tumour did not enhance and was excluded. The mean tumour SUVmax was 7.7 (range 2.4-26.1). The mean values for tumour perfusion, perfusion normalized to cardiac output, standard perfusion value (SPV) and permeability were 41 ml/min per 100 g (19-59 ml/min per 100 g), 0.56%/100 g (0.33-1.09%/100 g), 3.6 (2.5-5.9) and 0.15/min (0.09-0.30/min), respectively. Linear regression analysis showed a positive correlation between tumour SUV and tumour perfusion normalized to cardiac output (r=0.55, p=0.045) and a marginal correlation between tumour SUV and tumour SPV (r=0.19, p=0.065). There were no significant correlations between tumour SUV and tumour perfusion (r=0.29, p=0.401) or permeability (r=0.03, p=0.682).The first data from combined (18)F-FDG-PET/DCE-CT in breast cancer are reported. The technique was successful in eight of nine patients. Breast tumour metabolic and vascular parameters were consistent with previous data from (15)O-H(2)O-PET.

F-18 fluoro-2-deoxyglucose (F-18 FDG) positron emission tomography with computed tomography (PET/CT) is increasingly being used in the diagnosis of inflammatory disorders. We present a case of giant cell arteritis and polymyalgia rheumatica in a 64-year-old woman, identified on F-18 FDG PET/CT scanning during workup for an unknown primary tumor. This case highlights the importance of metabolic imaging in the assessment of extent and activity of large vessel vasculitis and related conditions.

A 57-year-old man with multiple myeloma had a rapidly enlarging mass in the right thyroid lobe for 6 months. Fine needle aspiration biopsy was performed, and cytologic examination revealed atypical plasma cells. One week later, the patient was referred for F-18 FDG imaging for further investigation and hyperactive foci on the right thyroid lobe were detected. We are reporting a case with extramedullary plasmacytoma of the thyroid detected on PET/CT scan.

This study was undertaken to estimate metabolic tissue properties from dynamic breast F-18-FDG PET/CT image series and to display them as 3D parametric images. Each temporal PET series was obtained immediately after injection of 10 mCi of F-18-FDG and consisted of fifty 1- minute frames. Each consecutive frame was nonrigidly registered to the first frame using a finite element method (FEM) based model and fiducial skin markers. Nonlinear curve fitting of activity vs. time based on a realistic two-compartment model was performed for each voxel of the volume. Curve fitting was accomplished by application of the Levenburg-Marquardt algorithm (LMA) that minimized X 2 . We evaluated which parameters are most suitable to determine the spatial extent and malignancy in suspicious lesions. In addition, Patlak modeling was applied to the data. A mixture model was constructed and provided a classification system for the breast tissue. It produced unbiased estimation of the spatial extent of the lesions. We conclude that nonrigid registration followed by voxel-by-voxel based nonlinear fitting to a realistic two-compartment model yields better quality parametric images, as compared to unprocessed dynamic breast PET time series. By comparison with the mixture model, we established that the total cumulated activity and maximum activity parametric images provide the best delineation of suspicious breast tissue lesions and hyperactive subregions within the lesion that cannot be discerned in unprocessed images.

Clinically metastases to the thyroid are rare with an autopsy series incidence ranging from 1.25% to as high as 24% in widespread malignancy. Although detection of metastasis to the thyroid gland often indicates poor prognosis, aggressive surgical and medical therapy may be effective in a small percentage of patients. In this article we describe F-18 FDG PET/CT images of metastases to the thyroid in a case of nasopharyngeal carcinoma (NPC). Because anaplastic NPC metastases to the thyroid are rare, it is important to make a correct diagnosis, so that appropriate treatment may be chosen.

Renal impairment secondary to lymphomatous parenchymal infiltration is uncommon. Early recognition of this cause of acute renal failure (ARF) is important as initiation of steroid therapy often results in rapid improvement in renal function. We highlight the usefulness of the functional asp

F-18 FDG PET/CT provides an accurate staging and post-therapeutic evaluation of melanoma based on high metabolic characteristics of its primary and secondary lesions. This functional imaging modality may, however, detect coexisting benign lesions of inflammatory or infectious origin mimicking malignancy thus interfering with the staging of cancer. The authors present a case of ruptured epidermal inclusion cyst exhibiting abnormal radiotracer accumulation on PET/CT in a patient with a history of recurrent metastatic melanoma.

We report a case where acute varicella infection, chickenpox, mimics the findings of recurrent Hodgkin disease on F-18 FDG PET/CT. A 28-year-old man with a history of Hodgkin disease in remission had fatigue, pyrexia, and a raised ESR. His F-18 FDG PET/CT, performed to exclude lymphoma recurrence, demonstrated FDG-avid lymphadenopathy and increased FDG uptake in his spleen. A day later he developed the generalized rash of acute varicella infection. This was managed with valacyclovir. Repeat F-18 FDG PET/CT done 1 month later showed no evidence of FDG-avid disease. In this patient the stimulation of an immune response by the acute viral infection mimics recurrent lymphoma.

A 48-year-old man with squamous-cell carcinoma of the left tonsillar fossa and cervical lymph node metastases was being staged before radiation and chemotherapy. The patient had periodontal disease, and extraction of 2 teeth was performed before therapy. A staging PET/CT was performed 1 week after extraction. This case demonstrates increased FDG uptake at the extraction sites, which could be potentially mistaken for metastatic lesions, especially without the fused PET/CT images.

Purpose There are approximately 32,000 new cases of thyroid carcinoma annually in the United States. F-18 FDG PET/CT has an established role in cancer management, including thyroid cancer, usually in patients who are thyroglobulin (Tg) positive/iodine negative. We reviewed our experience with F-18 FDG PET/CT in thyroid cancer, with an emphasis on correlation with Tg, and maximum standardized uptake values (SUV). We also analyzed the role of thyroid stimulating hormone (TSH) on PET/CT results. Materials and methods This is a retrospective study (January 2003 to December 2006) of 76 patients with differentiated thyroid cancer, who had F-18 FDG PET/CT scans. There were 44 women and 32 men, with age range of 20 to 81 years (average, 51.1 +/- 18.1). The administered doses of F-18 FDG ranged from 396 to 717 MBq (15.8-19.4 mCi) (average, 566 +/- 74.8) (15.3 +/- 2). Reinterpretation of the imaging studies for accuracy and data analysis from medical records were performed. Results A total of 98 PET/CT scans were analyzed (59 patients had 1 scan, 12 patients had 2, and 5 patients had 3). PET/CT was 88.6% sensitive (95% CI: 78.-94.3) and 89.3% specific (95% CI: 71.9-97.1). Mean Tg level was 1203 ng/mL (range, 0.5-28,357) in patients with positive PET/CT and 9.72 ng/mL (range, 0.5-123.0) in patients with negative PET/CT scans (P = 0.0389). Mean SUV max was 10.8 (range, 2.5-32) in the thyroid bed recurrence/residual disease and 7.53 (range, 2.5-26.2) in metastatic lesions (P = 0.0114). Mean SUV max in recurrent/residual disease in patients with TSH 30 mIU/L was 8.1 (range, 2.6-32) (P = 0.2994). Conclusion F-18 FDG PET/CT had excellent sensitivity (88.6%) and specificity (89.3%) in this patient population. Metastatic lesions were reliably identified, but were less F-18 FDG avid than recurrence/residual disease in the thyroid bed. TSH levels at the time of PET/CT did not appear to impact the FDG uptake in the lesions or the ability to detect disease. In the setting of high or rising levels of Tg, our study confirms that it is indicated to include PET/CT in the management of patients with differentiated thyroid cancer.

A 48-year-old woman without any symptoms found multiple enlarged lymph nodes in the neck and axillae for 1 year. F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET)–computed tomography (CT) was performed to define the diagnosis and showed avid FDG uptake in the enlarged lymph n

An adrenal metastasis was identified on an F-18 FDG PET/CT scan in a patient with anaplastic thyroid cancer. There are very few reports of thyroid cancer, even anaplastic thyroid cancer, metastasizing to the adrenal.

Mucoepidermoid carcinomas in the bronchial tree are extremely rare tumors. Such tumors are classified into low-grade and high-grade on the basis of histological criteria. Fluorine-18-fluorodeoxyglucose positron emission tomography (F-18 FDG PET) is a useful technique for the evaluation of pulmonary lesions; however, to our knowledge, F-18 FDG PET findings in mucoepidermoid carcinoma of the bronchus have been described in only a few cases. Identifiable focal F-18 FDG uptake has been reported in high-grade mucoepidermoid carcinoma, but it is unclear whether F-18 FDG accumulates in low-grade mucoepidermoid carcinoma. Here, we present the case of a 37-year-old woman, with pathologically proven low-grade mucoepidermoid carcinoma, who underwent high-resolution computed tomography (CT) and F-18 FDG PET/CT before treatment.

A 27-year-old white man was diagnosed with a testicular, metastatic germ cell tumor. The patient was evaluated with F-18 fluorodeoxyglucose positron emission tomography and coregistered computed tomography (FDG PET/CT) as well as a contrast-enhanced CT (CECT) of the abdomen and pelvis. Serologic tests were performed. At laparoscopic appendectomy, findings were consistent with acute suppurative appendicitis. This case exemplifies the relevance of incidental findings detected on FDG PET/CT.

Coccidioidomycosis is an endemic fungal disease in the southwestern regions of the North American continent. It is contracted by accidental inhalation of coccidioidal arthrospores with predominant pulmonary pathology. Lung nodules and masses may mimic cancer on cross-sectional or PET imagin

A 62-year-old woman who had surgery for carcinoma of the left breast (infiltrating duct cell carcinoma grade III) and was postchemotherapy and local radiotherapy presented after 10 years with severe pain in the left shoulder and left arm. Routine follow-up investigations in these 10 years h

Melanomas usually metastasize through the lymphatic route. However, choroidal melanoma invariably disseminates hematogenously to the liver. Liver metastasis develops in approximately two thirds of patients with recurrent uveal melanoma. The PET scan is a sensitive tool for the detection and localization of hepatic and extrahepatic metastatic choroidal melanoma. We report a patient with a history of choroidal melanoma in the left eye. The patient had undergone a scleral plaque placement followed by an enucleation and an implant. He was referred to us for a PET scan for restaging. No prior PET scan was available for comparison. An implant in the eye with intense FDG-avid liver metastasis should raise suspicion of choroidal melanoma.

We present a case of a 74-year-old man with a history of a known 4.3-cm abdominal aortic aneurysm (AAA) and recent sigmoid colectomy for colon cancer who presented with Staphylococcus aureus bacteremia, renal failure, and low-grade fever. The likely source of his bacteremia was an infected

(2013). Large-vessel giant cell arteritis Fever of unknown origin in a patient with a prosthetic valve. Acta Cardiologica: Vol. 68, No. 5, pp. 529-530.

Fluorine-18 fluoro-deoxy-glucose positron emission tomography (F-18 FDG PET) is not sensitive modality for the diagnosis of primary hepatocellular carcinoma (HCC). However, FDG-PET imaging may be useful in the identification of extrahepatic metastases. We report an interesting image of HCC with solitary metastasis to sternum detected by F-18 FDG PET/CT.

F-18 FDG PET/CT has become a useful technique in the evaluation of pulmonary lesions. We present a case of markedly increased and diffuse pulmonary F-18 FDG activity in a patient with acute respiratory distress syndrome (ARDS). High rates of glucose utilization by the inflammatory cells involved in the pathogenesis of ARDS might explain the increased pulmonary F-18 FDG uptake we observed. In the proper clinical setting, ARDS should be considered in the differential diagnosis of patients with diffusely increased F-18 FDG activity in the lungs.

WOS: 000294486500037 PubMed: 21892061 An asymptomatic 68-year-old man with suspected prostate cancer was referred for F-18 FDG PET/CT imaging for characterization of an incidental solitary pulmonary nodule. The left lingular nodule demonstrated corresponding hypermetabolic activity. Histopathologic diagnosis from transbronchial tissue biopsy disclosed anthracotic lung tissue with congestion. Although anthracosis is a form of pneumoconiosis typically observed in coal workers, in this patient, exposure to fuel exhaust and prior smoking seemed to be the only risk factors. Anthracotic nodule should be added to the list of causes for F-18 FDG active pulmonary lesions.

We report a case of a 78-year-old man with a left apical lung mass suspected to be an adenocarcinoma previously evaluated by thorax computed tomography, who underwent F-18 FDG PET/CT as a staging study. It revealed the unexpected presence of 3 congenital kidneys, 1 on the left side and 2 on

This report of an 82-year-old man who presented with a 3-week history of an enlarging left axillary mass and mild fevers, highlights the usefulness of both gallium-67 and F-18 FDG PET/CT imaging in the staging of histiocytic sarcoma. While PET/CT was superior in determining the extent of the disease, gallium can be used to help stage the disease in centers where PET/CT is not available.

Pancreatic involvement by metastasis from other primaries is rare and accounts for approximately 2% to 4% of pancreatic tumors. In this article, we describe FDG-avid pancreatic involvement in a patient with diagnosis of breast cancer. We conclude that FDG PET can be a convenient noninvasive method of early detection of recurrence and in monitoring metastatic disease during follow-up in such patients. A positive FDG PET warrants histopathologic correlation for appropriate treatment.

Hemangiopericytoma is an unusual tumor that arises from vascular smooth muscle cells. It is mainly experienced in 4th to 5th decades of life and soft-tissue masses are frequently located in lower extremity, pelvis, and retroperitoneum. A 29-year-old man presented with a mass lesion in the right nasal cavity associated with shortness of breath as a result of nasal obstruction. An incisional biopsy was reported as sinonasal type hemangiopericytoma. The initial staging F-18 flourodeoxyglucose PET/CT successfully demonstrated severe hypermetabolism in the primary tumor location and mild-to-moderate hypermetabolism in the right upper jugular lymph node.

Corresponding Author: Michael Schmuecking, MD E-Mail: michael.schmuecking@insel.ch Inclusion criteria: Informed consent, histologically proven NSCLC stage I or hypermetabolic oligometastatic lung lesions. Peripheral or central localization, maximal tumor diameter of 45mm. Karnofsky index > 60%. Medically inoperable. Moving of the lung lesion during breathing less than 5mm as detected by 4D-CT. Initial staging: whole body 18F-FDG PET/CT in radiation treatment position, MRI of the brain. Optional for staging: 18F-FDG PET/CT of the lung in breath hold technique in radiation treatment position. Radiation treatment planning: 4D-CT and angio-CT in radiation treatment position for target volume delineation. BodyFIX® vacuum cushions for comfortable, accurate and reproducible patient positioning during radiation treatment. Using 4DCT for target volume delineation, a Boolean operation was used to sum the multiple gross target volumes (GTV) delineated in diagnostic lung window to form an internal target volume (ITV). The planning target volume was derived by a three-dimensional isotropic expansion of the ITV by 5mm to account for both microscopic extension and daily setup errors. Using non-gated PET/CT (frame mode) for target volume delineation of the ITV the iso-line of SUV 2.5 was used or the tumor/background algorithm as proposed by Nestle et al. JNM 2005. For 16/22 lung lesions the prescription dose was 5 x 12 Gy, for 1/22 centrally located lung lesion the prescription dose was 5 x 10 Gy, for the initial 5/22 lesions the prescription dose was 5 x 7 Gy. For all patients the prescription isodose was the 80% line (prescription line identical with the planning target volume). Maximal time for follow-up: 21 months, mean time for follow-up: 13 months. By design, stereotactic body radiotherapy (SBRT) is applied to small treatment volumes, using fewer but significantly higher dose fractions, and steep dose gradients – all of which act to maximize cell kill and minimize the risk of damage to the surrounding normal tissues.

We present the F-18 FDG and ¹¹C-choline PET/CT images obtained in 2 cases of hemangioblastoma. Hemangioblastoma is a highly vascular benign tumor that typically arises in the cerebellum or spine. The characteristic findings of a hemangioblastoma on both CT and MR include a peripherally located cerebellar lesion with a central cystic region and a peripherally enhanced nodule. In both patients, the uptake in the lesion was relatively low on the F-18 FDG PET/CT images and relatively high on the ¹¹C-choline PET/CT images.

We present a case of carcinoma cervix found to have a soft tissue lesion in retroperitoneal region with intense FDG uptake. However, this FDG uptake was false positive as the final diagnosis was retroperitoneal fibrosis.

A 35-year-old woman, having recurrent pain after total elbow arthroplasty, was subjected to positron emission tomography/computed tomography with fluorodeoxyglucose (FDG PET/CT) to rule out infected orthopedic hardware. A diagnosis of aseptic loosening was made based on the gram staining and 9 months of clinical follow-up. This case report highlights the utility of FDG PET/CT in evaluation of painful elbow prostheses and describes the FDG uptake pattern in confirmed case of aseptic loosening.

We present the case of a 64-year-old woman who suffered from occasional right upper abdominal pain for several months. Both abdominal ultrasonography and magnetic resonance imaging showed a hepatic mass of indeterminate nature. F-18 FDG PET/CT showed a solitary hypermetabolic mass in the liver; a malignancy was therefore suspected. Her hepatic tumor was resected; it was a solitary necrotic nodule with larval infestation but no evidence of malignancy.