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In addition to gastroenteropancreatic neuroendocrine neoplasms, a wide variety of tumors express somatostatin receptors. Somatostatin receptor imaging, heavily utilized in neuroendocrine oncology, may also have utility in the diagnosis of other neoplasms and raises the possibility of potential therapeutic options. We describe the case of a 60-year-old man who underwent 68Ga-DOTATATE PET/CT, demonstrating an avid invasive pituitary macroadenoma. This mass was persistent and refractory despite traditional treatment options. Because of the avidity, 177Lu-DOTATATE therapy was offered, although not ultimately performed, demonstrating a potential treatment for challenging cases utilizing the principles of theranostics.

Adrenal lesions are routinely encountered incidentally in clinical practice. Although most of these lesions are benign, malignancy needs to be excluded. Therefore, the initial clinical workup is to exclude aggressive characteristics suggesting malignancy and to identify characteristics predictive of the most common benign lesion, an adrenal adenoma. Predicting a benign adenoma using a variety of imaging modalities has been widely studied using unenhanced computed tomography (CT), contrast enhanced CT, and magnetic resonance (MR) imaging. This review article describes the currently used imaging protocols and clinical interpretation criteria of common adrenal lesions. An adenoma can be predicted if a homogenous soft tissue adrenal mass demonstrates low attenuation (upper threshold value of 10 Hounsfield Units) on unenhanced CT, demonstrates an absolute enhancement washout of ≥ 60% and/or relative enhancement washout of ≥ 40% on adrenal washout contrast enhanced CT, or demonstrates signal loss in opposed-phased MR imaging. If an adrenal adenoma cannot be predicted based upon these criteria, the lesion should be evaluated for other imaging characteristics that suggest a specific pathology, such as an adrenal cyst or myelolipoma. Although nonspecific and with limitations, 18F-fluorodeoxyglucose (FDG) PET/CT has a potential role for differentiating benign from malignant lesions based upon the amount of radiopharmaceutical uptake with malignant lesions generally having greater uptake. If clinical and/or hormonal screening suggests a pheochromocytoma, consideration can be given to 18F-dihydroxyphenylalanine (DOPA) or 123I-metaiodobenzylguanidine (MIBG) in addition to CT and MR. Finally, this review proposes a diagnostic work-up strategy for routine use in clinical practice.

Sites of infection and inflammation can be misleading in oncology PET/CT imaging because these areas commonly show 18F-FDG activity. Caution in the interpretation must be taken to avoid the misdiagnosis of malignancy. Utilization of both CT findings as well as patient history can help differentiate benign infectious and inflammatory processes from malignancy, although occasionally additional work-up may be required. This article discusses the mechanism of 18F-FDG uptake in infection and inflammation with illustrative examples.

Purpose: Hyperglycemia affects FDG uptake in the brain, potentially emulating Alzheimer’s disease in normal individuals. This study investigates global and regional cerebral FDG uptake as a function of plasma glucose in a cohort of patients. Methods: 120 consecutive male patients with FDG PET/CT for initial oncologic staging (July–Dec 2015) were reviewed. Patients with dementia, cerebrovascular accident, structural brain lesion, prior oncology treatment or high metabolic tumor burden (recently shown affecting brain FDG uptake) were excluded. 53 (24 nondiabetic) eligible patients (age 65.7 ± 2.8 mean ± SE) were analyzed with parametric computer software, MIMneuro™. Regional Z-scores were evaluated as a function of plasma glucose and age using multi variable linear mixed effects models with false discovery analysis adjusting for multiple comparisons. If the regression slope was significantly (p

OBJECTIVE: Frostbite is a localized cold-thermal injury resulting from prolonged exposure of flesh to freezing and near freezing temperatures. The depth and extent of frostbite injuries are not easily assessed, from a clinical standpoint, at the time of injury making it challenging to plan appropriate management and treatment. METHODS: A review of the literature of management of cold-related injuries and retrospective case review of the imaging and clinical course of frostbite injury. RESULTS: Bone scintigraphy with single photon emission computed tomography (SPECT)/CT was performed in the acute and subacute course of frostbite injuries, subsequently leading to earlier definitive management and shorter hospital stay. CONCLUSION: Multiphase technetium-99m-methylenediphosphonate ((99)mTc-MDP) bone scintigraphy with SPECT/CT can expedite clinical management of frostbite injuries by determining the extent of injury and can accurately predict the level of amputation if needed. ADVANCES IN KNOWLEDGE: SPECT/CT is underutilized at many facilities but can have a profound and immediate impact on clinical management of patients with frostbite when used in combination with physiological bone scan imaging.

Painful osseous metastasis resulting from castration-resistant prostate carcinoma is a common clinical problem. Historically, nuclear medicine offered several palliative beta-emitting radiopharmaceuticals targeting the skeleton with the goal of decreasing pain. However, these have largely been replaced by the alpha-emitting agent 223radium (Ra). 223Ra received Food and Drug Administration approval in 2013 for the treatment of metastatic castration-resistant prostate cancer with symptomatic bone metastases without visceral metastases. 223Ra offers an improved therapeutic profile due to its alpha-particle emissions resulting in a relatively higher linear energy transfer and lower particle range compared with beta-emitters. 223Ra also has demonstrated to increase overall survival in patients and to delay adverse skeletal events. Running a successful clinical nuclear therapy program with Ra requires a multidisciplinary team approach and this article suggests an implementation strategy from the authors' institution. Potential new nuclear radiopharmaceuticals still under investigation offering the future possibility of radioligand therapy are also discussed briefly.

Vesicoureteral reflux after renal transplantation is associated with increase risk of urinary tract infections, renal scarring, and graft failure. We describe a case of a 46-year-old woman with 2 transplant kidneys, one functioning and another nonfunctioning, presenting with pelvic pain after a bilateral periureteral bulking procedure. Diuretic renography was performed to exclude iatrogenic ureteral obstruction. This showed a normally functioning transplant kidney without obstruction and subsequent vesicoureteral reflux into the collecting system of the nonfunctioning transplant kidney. This inadvertent indirect nuclear cystogram illustrates an unusual imaging presentation of a common disease process requiring further treatment.

Purpose To examine the effect metabolic burden (tumor and/or cardiac myocyte uptake) has on fluorine 18 fluorodeoxyglucose (FDG) distribution in organs and tissues of interest. Materials and Methods Positron emission tomographic (PET)/computed tomographic (CT) scans at the Ann Arbor Veterans Affairs hospital from January to July 2015 were reviewed. A total of 107 scans (50 patients; mean age, 64.3 years ± 13.2 [standard deviation]) had metabolic tissue burden assessed by using total lesion glycolysis (TLG) obtained from autosegmentation of the tumor and/or cardiac tissue. Standardized uptake value (SUV) and subsequent normalized SUV uptake in target organs and tissues were compared with 436 FDG PET/CT scans previously reported in 229 patients as a function of TLG to describe the effect(s) that metabolic burden has on reference tissue (blood pool, liver, and brain) FDG uptake. Subsequent regression by using linear mixed-effects models was used. If the slope of the regression was significantly (P.05) different than zero, then an effect from TLG was present. Results There was a negative inverse relationship (P.0001) between FDG uptake within reference tissues (blood pool, liver, and brain) and TLG in comparison to the study population at similar blood glucose levels. This TLG effect was no longer statistically significant (P.05) when FDG uptake was normalized to a reference tissue (eg, blood pool or liver). Conclusion Metabolic tissue burden can have a significant effect on SUV measurements for PET imaging. This effect can be mitigated by normalizing FDG uptake to a reference tissue.

In addition to nuclear cardiac and breast imaging, Tc-sestamibi scintigraphy is often used to localize parathyroid adenomas. F- fluorodeoxyglucose (FDG) PET is heavily utilized in oncology, although its use in identifying parathyroid adenomas is limited. We describe a case of a 57-year-old woman who underwent parathyroid scintigraphy and F-FDG PET/CT in the same week due to hyperparathyroidism and an enlarging breast mass, respectively. A right paratracheal mediastinal mass that otherwise would be suspicious for nodal metastases by CT alone was correctly identified to be an ectopic parathyroid adenoma using a combination of the nuclear medicine studies performed.

Objectives: To describe a rare case of subcutaneous panniculitis-like T-cell lymphoma (SPTCL) with morphologic and immunophenotypic evidence of bone marrow involvement. Methods: Biopsy specimens of skin and subcutis and bone marrow were examined using H&E-stained sections. Immunohistochemical studies for CD2, CD3, CD4, CD5, CD7, CD8, CD20, CD30, CD56, and granzyme B were reviewed. In addition, T-cell receptor γ gene rearrangement studies were performed. Results: A bone marrow core biopsy demonstrated several lymphohistiocytic aggregates containing atypical, cytotoxic T cells that rimmed adipocytes and were associated with karyorrhexis. These T cells were morphologically and immunophenotypically identical to a concurrent SPTCL, expressing CD2, CD3, CD7, CD8, and granzyme B but with diminished CD5 expression. Conclusions: SPTCL may rarely involve the bone marrow. Bone marrow infiltrates show a similar morphologic and immunophenotypic appearance to those in the subcutaneous fibroadipose tissue, including rimming of adipocytes by neoplastic lymphocytes.

The purpose of this study was to systematically review the utility of single-photon emission tomography–computed tomography (SPET–CT) fusion imaging in the investigation of thyroid cancer. We performed a systematic search of the world literature on radionuclide SPET–CT imaging of thyroid cancer using the medical databases Medline (OVID) and PubMed. The following search terms were used to identify relevant studies: (a) thyroid, combined with (b) SPECT/CT or SPECT–CT or SPET/CT or SPET–CT. The electronic searches returned citations for 1,189 potentially eligible articles and 98 abstracts were reviewed for relevance by two co-authors. Thirty-one peer-reviewed full articles reporting the utility, value and diagnostic performance of radioiodine SPET–CT for the imaging of well-differentiated thyroid cancer were selected. The quality of these studies was assessed using the quality assessment of diagnostic accuracy studies-2 tool. As there was heterogeneity in the studies, a systematic review analysis was conducted as our chosen research synthesis method. A total of 31 studies published between 2003 and 2014 report the utility of radioiodine SPET–CT. These studies uniformly found incremental diagnostic value of I-123 and I-131 SPET–CT over SPET and/or planar imaging. SPET–CT allows accurate characterization of radioiodine uptake in the neck and at distant sites, clarifies equivocal foci of radioactivity, improves specificity for disease, and evaluates benign physiological etiologies. Additional pilot uses of SPET–CT have been reported, e.g., for thyroid nodule evaluation, medullary thyroid cancer work-up, and investigation of lingual thyroid. Radioiodine SPET–CT fusion imaging of thyroid cancer has incremental utility, improving image interpretation as compared to planar and SPET imaging. It is likely to see more widespread application in the future.

Sites of infection and inflammation can be misleading in oncology PET/CT imaging because these areas commonly show 18F-FDG activity. Caution in the interpretation must be taken to avoid the misdiagnosis of malignancy. Utilization of both CT findings as well as patient history can help differentiate benign infectious and inflammatory processes from malignancy, although occasionally additional work-up may be required. This article discusses the mechanism of 18F-FDG uptake in infection and inflammation with illustrative examples.

OBJECTIVE. Extraosseous radioactivity outside of the expected biodistribution is often encountered on 99mTc–methylene diphosphate (MDP) bone scintigraphy, and proper interpretation requires an understanding of the mechanisms underlying this uptake and knowledge of the possible causes, depending on the site or structure involved. CONCLUSION. We present examples of extraosseous radiotracer uptake seen on 99mTc-MDP bone scans in which either SPECT with integrated CT or correlative imaging improved the study's interpretation.

PET/CT with (18)F-fluorodeoxyglucose (FDG) or using different radiocompounds has proven accuracy for detection of adrenal metastases in patients undergoing cancer staging. It can assist the diagnostic work-up in oncology patients by identifying distant metastases to the adrenal(s) and defining oligometastatic disease that may benefit from targeted intervention. In patients with incidentally discovered adrenal nodules, so-called adrenal "incidentaloma" FDG PET/CT is emerging as a useful test to distinguish benign from malignant etiology. Current published evidence suggests a role for FDG PET/CT in assessing the malignant potential of an adrenal lesion that has been 'indeterminately' categorized with unenhanced CT, adrenal protocol contrast-enhanced CT, or chemical-shift MRI. FDG PET/CT could be used to stratify patients with higher risk of malignancy for surgical intervention, while recommending surveillance for adrenal masses with low malignant potential. There are caveats for interpretation of the metabolic activity of an adrenal nodule on PET/CT that may lead to false-positive and false-negative interpretation. Adrenal lesions represent a wide spectrum of etiologies, and the typical appearances on PET/CT are still being described, therefore our goal was to summarize the current diagnostic strategies for evaluation of adrenal lesions and present metabolic and anatomic appearances of common and uncommon adrenal lesions. In spite of the emerging role of PET/CT to differentiate benign from malignant adrenal mass, especially in difficult cases, it should be emphasized that PET/CT is not needed for most patients and that many diagnostic problems can be resolved by CT and/or MR imaging.