The novel Gallium-68 prostate-specific membrane antigen (PSMA)-bis [2-hydroxy-5-(carboxyethyl)benzyl] ethylenediamine-diacetic acid positron emission tomography (PET) tracer is increasingly used in the evaluation of prostate cancer, particularly in the detection of recurrent disease. However, PSMA is expressed in nonprostatic tissues, as well as in other pathologic conditions. Here we illustrate such interpretive pitfalls with relevant images that one may encounter while reporting PSMA PET/CT. This study aims to show variation in physiological distribution of PSMA activity and uptake in various benign and neoplastic disorders that may be misinterpreted as prostatic metastatic disease. These pitfalls are illustrated to enhance awareness, aiding a more accurate interpretation of the study. Retrospective database of all (68)Ga PSMA PET/CT was created and reviewed. In total, 1115 PSMA PET/CT studies performed between February 27, 2015, and May 31, 2017, were reviewed. Any unusual uptake of PSMA was documented, described, and followed up. All cases were then subdivided into the following 4 categories: physiological uptake, benign pathological uptake, nonprostatic neoplastic uptake, and miscellaneous uptake. A variety of nonprostatic tissues and lesions, including accessory salivary gland, celiac ganglion, gall bladder, Paget's bone disease, reactive lymph nodes, non–small cell lung cancer, renal cell cancer, and neuroendocrine tumor, were found to show PSMA uptake. PSMA uptake is not prostate-specific and can be taken up physiologically and pathologically in nonprostatic tissue. It is important for reporting physicians to recognize these findings and instigate appropriate investigations when required while avoiding unnecessary procedures in physiological variation.

F-FDG PET/CT plays an integral role in the diagnosis of cardiac sarcoidosis. Diagnostic accuracy is affected by fasting duration and means of cardiomyocyte glucose uptake suppression before scanning.

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Abstract. Geographic location of a person is important contextual information that can be used in a variety of scenarios like disaster relief, directional assistance, context-based advertisements, etc. GPS provides accurate localization outdoors but is not useful inside buildings. We propose an coarse indoor localization approach that exploits the ubiquity of smart phones with embedded sensors. GPS is used to find the building in which the user is present. The Accelerometers are used to recognize the user's dynamic activities (going up or down stairs or an elevator) to determine his/her location within the building. We demonstrate the ability to estimate the floor-level of a user. We compare two techniques for activity classification, one is naive Bayes classifier and the other is based on dynamic time warping. The design and implementation of a localization application on the HTC G1 platform running Google Android is also presented.

A 66-year-old man with history of prostate carcinoma underwent Ga-labeled prostate-specific membrane antigen PET/CT for surveillance of rising prostate-specific antigen. Intense tracer uptake was noted in segments 2, 7, and 8 of the liver. The lesions were not FDG avid on F-FDG PET/CT. Further characterization with magnetic resonance cholangiopancreatography with Gd-EOB (Primovist) contrast revealed ill-defined arterially enhancing lesions with central washout in the venous phase. CT-guided core biopsy was performed, and histopathology confirmed well-differentiated hepatocellular carcinoma.

Ga-PSMA PET/CT is increasingly used to evaluate recurrent prostatic malignancy due to its high specificity. A 75-year-old man with a previous history of treated prostate cancer 3 years earlier presented with rising prostate-specific antigen (PSA) level and underwent Ga-PSMA PET/CT which demonstrated a PSMA-avid focus in the neck of the pancreas. Triple-phase abdominal CT demonstrated enhancement in the arterial phase and to a lesser extent the venous phase of a soft tissue mass in the neck of the pancreas. Cytological and histopathological examination of the soft tissue mass confirmed a low-grade pancreatic neuroendocrine tumor.

A 50-year-old man with recently diagnosed prostate cancer was referred for Ga-prostate-specific membrane antigen (PSMA) PET/CT with elevated prostate-specific antigen. PET/CT demonstrated increased PSMA uptake in an undisplaced transverse fracture of the L1 vertebral body. This case illustrates that PSMA uptake can occur in a transverse vertebral body fracture and is a benign cause of PSMA uptake.

A 68-year-old man with treated prostate cancer 3 years earlier and small cleaved B-cell follicular lymphoma diagnosed 1 year prior and monitored clinically with no active intervention ("watch and wait" approach) was referred for Ga-prostate-specific membrane antigen (PSMA) PET/CT with rising prostate-specific antigen level. PET/CT demonstrated diffuse PSMA uptake in the prostate (SUVmax 3.6) and multiple PSMA-avid nonenlarged lymph nodes. Moderate PSMA uptake (SUVmax 4.7) was also noted in an enlarged right inguinal lymph node (SUVmax 4.7), which on core biopsy confirmed small cleaved B-cell follicular lymphoma.