PET and PET/CT with 68gallium-labeled somatostatin analogues in Non GEP-NETs Tumors.

Somatostatin (SST) is a 28-amino-acid cyclic neuropeptide mainly secreted by neurons and endocrine cells. A major interest for SST receptors (SSTR) as target for in vivo diagnostic and therapeutic purposes was born since a series of stable synthetic SST-analouges PET became available, being the native somatostatin non feasible for clinical use due to the very low metabolic stability. The rationale for the employment of SST-analogues to image cancer is both based on the expression of SSTR by tumor and on the high affinity of these compounds for SSTR. The primary indication of SST-analogues imaging is for neuroendocrine tumors (NETs), which usually express a high density of SSTR, so they can be effectively targeted and visualized with radiolabeled SST-analogues in vivo. Particularly, SST-analogues imaging has been widely employed in gastroenteropancreatic (GEP) NETs. Nevertheless, a variety of tumors other than NETs expresses SSTR thus SST-analogues imaging can also be used in these tumors, particularly if treatment with radiolabeled therapeutic SST-analouges PET is being considered. The aim of this paper is to provide a concise overview of the role of positron emission tomography/computed tomography (PET/CT) with (68)Ga-radiolabeled SST-analouges PET in tumors other than GEP-NETs.

A 79-Year-Old Man With Interstitial Lung Disease and Cryptic Area of High 18 Fluorodeoxyglucose Uptake in Left Upper Lobe.

Seven years after left hemicolectomy and radical lymph nodal dissection followed by adjuvant chemotherapy for colorectal cancer (histotype, adenocarcinoma; stage, pT3N2M0; grading, G2), a slight increase in carcinoembryonic antigen levels (6.2 ng/mL; range, 0-5 ng/mL) was detected in a 79-year-old man. He was a heavy smoker with history of an interstitial fibrotic lung disease with associated areas of emphysema.