The clinical characteristics and prognosis of 73 patients with Nonfunctional Gastroenteropancreatic neuroendocrine neoplasm: a 10-year retrospective study of a single center

Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) which originated from peptidergic neurons of the digestive tract and neuroendocrine cells constitute a rare and heterogeneous group of tumors with varied biology. Because of the concealment of symptoms in mostly nonfunctional GEP-NENs, the difficult early diagnosis challenging reduced the chances of curative surgery, and decreased patients’ survival. This study analyzed 73 patients diagnosed with nonfunctional GEP-NENs between July 2004 and May 2015, including the clinical characteristics, treatment outcome and survival of patients, which aimed to prepare a practical guide to be used in common clinical practice. SPSS 17.0 was use to analyze the statistical significance. The median age of the 73 patients was 58 years, 50 were men. 5 patients were classified as NEN G1 (n=5; 6.8%), 6 were G2 (n=6; 8.2%), 43 were neuroendocrine carcinoma (NEC) (n=43; 58.9%), and 19 were MANEC (n=19; 26.0%). Most cases were diagnosed with III-IV tumors at presentation (n=42; 57.5%), although the majority of well-differentiated GEP-NENs (G1 and G2) were diagnosed with earlier stage I and II (n=7; 70%). Operation based on comprehensive treatment were performed in most patients (n=64; 87.7%), while the other 9 cases underwent radiotherapy or chemotherapy simply. The median follow-up period was 37 months. The overall 3-year and 5-year survival were 76.9% and 40.5%. In the univariate analysis, higher stage according to the AJCC/UICC classification (P