PET and PETCT with 68Gallium-Labeled Somatostatin Analogues in Non GEP-NETs Tumors

Abstract EN

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 68Ga-radiolabeled SST-analouges PET in tumors other than GEP-NETs.