Clinicopathologic characteristics and prognosis of gastroenteropancreatic neuroendocrine neoplasms: a multicenter study in South China

Abstract Background Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) are a heterogeneous group of rare tumors. Many issues in terms of epidemiologic features, pathogenesis, and treatment of GEP-NENs are still under discussion. Our study aimed to analyze the clinicopathologic characteristics and prognosis of Chinese patients with GEP-NENs. Methods Complete clinicopathologic data and survival information of 1183 patients with GEP-NENs treated between 2005 and 2015 were collected from five medical centers in Guangdong Province, China. Patient survival was estimated using the Kaplan–Meier method and analyzed using the log-rank test; prognostic factors were analyzed using the Cox proportional hazards model. Results The most common tumor location was the rectum (37.4%), followed by the pancreas (28.1%), stomach (20.7%), small intestine (7.2%), appendix (3.4%), and colon (3.3%). After initial definitive diagnosis, 1016 (85.9%) patients underwent surgery. The 1-, 3-, and 5-year overall survival (OS) rates for the entire cohort were 87.9%, 78.5%, and 72.8%, respectively. The 3-year OS rates of patients with G1, G2, and G3 tumors were 93.1%, 82.7%, and 43.1%, respectively (P