Radiolabeled somatostatin analogs for radionuclide imaging and therapy in patients with gastroenteropancreatic neuroendocrine tumors.

Gastroenteropancreatic neuroendocrine tumours (GEP-NETs) are a rare type of cancer that can arise from the diffused endocrine system, located in the gastrointestinal (GI) tract (carcinoids) and in the pancreas (insular tumors). Approximately 2% of all malignant tumours of the gastrointestinal system are GEP-NETs which can express somatostatin receptors. 111In-pentetreotide (octreoscan) and 68Ga-DOTA NOC (68Ga-labelled [1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid]-1-Nal3-Octreotide) are the commonly used radiopharmaceuticals for imaging. Once localized using 68Ga DOTA NOC or octreoscan, these tumours can be successfully targeted with radiolabelled somatostatin analogues. This review focuses on common nuclear medicine procedures used in both imaging and treatment of these tumors.