We report on a case of biopsy-proven and MRI-staged rectal carcinoma with avid prostate-specific membrane antigen (prostate-specific membrane antigen) uptake on Ga PET/CT as part of the workup for synchronous prostate cancer. This case adds to the growing number of observational reports on the presence of significant nonprostatic prostate-specific membrane antigen activity in malignant tumors and highlights the need for careful interpretation of unsuspected sites.

We present a case of primary cardiac lymphoma (PCL) that was initially manifest through syncopal episodes. In the diagnostic evaluation, positron emission tomography combined with computed tomography (PET-CT) made a significant contribution--beyond that which would have been possible if only conventional imaging modalities such as magnetic resonance imaging (MRI) and transthoracic echocardiography (TTE) were utilized--and played a major role in follow-up.

A 6-year-old male child with proteus syndrome and intractable epilepsy underwent ictal brain single photon emission computed tomography (SPECT) imaging with Tc-99m-labeled ethyl cysteinate dimer to identify an epileptic focus and further aid surgical planning. Magnetic resonance imaging (MRI) demonstrated extensive anatomic abnormalities. SPECT and MRI fusion images following injection of Tc-99m ethyl cysteinate dimer within 60 seconds from the onset of seizure activity clearly demonstrated a hyperperfused focus within the left temporal lobe laterally. This case illustrates the utility of ictal SPECT and MRI fusion in accurately localizing a potentially small seizure focus in a grossly abnormal brain.

This is a case of an unsuspected synchronous gastric schwannoma demonstrating increased F-FDG accumulation on PET/CT in a 65-year-old female patient diagnosed with non-Hodgkin lymphoma on the basis of different metabolic activity to other sites of disease at staging and discordant metabolic response to therapy. The gastric schwannoma was confirmed by histopathology and immunohistochemistry after surgical resection. This case adds to the limited literature on FDG-avid gastric schwannoma and highlights the importance of investigating differential metabolic activity and response on serial PET/CT imaging.

A limited 'above-diaphragm' scan for early assessment following chemoradiotherapy may be safely considered. The benefits of this tailored approach flow onto both the health system and the patients as it can improve resource allocation by increasing scanner availability and patient throughput and reduces cumulative patient radiation exposure.