Advances in the treatment of gastroenteropancreatic neuroendocrine neoplasms with somatostatin analogs

Neuroendocrine neoplasms (NENs) include well-differentiated neuroendocrine tumors (NETs) and poorly differentiated neuroendocrine carcinomas (NECs). Somatostatin receptors (SSTRs) are highly expressed on NETs cells, and somatostatin analogs (SSAs) could bind to SSTRs with high affinities, regulating cell proliferation and hormone secretion. As many clinical trials have demonstrated the antiproliferative efficacy and safety of SSAs in metastatic gastroenteropancreatic NETs (GEP-NETs), SSAs have been recommended by multiple NEN guidelines as the first-line therapy of GEP-NETs. In recent years, more and more researches have been exploring new therapeutic possibilities of SSA in GEP-NETs, such as high-dose SSA as second-line therapy, SSA in metastatic GEP-NETs with Ki-67 > 10%, SSA as adjuvant therapy for postoperative pancreatic NETs patients, and combinations of SSA with chemotherapy or targeted therapy. In this review, we summarized the latest published or released researches and discussed new application attempts of SSA in GEP-NETs.