OBJECTIVETo analyze the clinicopathological features and prognostic factors of gastric neuroendocrine carcinoma(NEC) based on a multicenter database from five medical centers in Southern China.

METHODSClinical and pathological data of 1 183 gastroenteropancreatic neuroendocrine neoplasms patients between January 2006 and December 2015 from five centers were retrospectively analyzed. A total of 156 gastric NEC cases(13.2%) with complete follow-up information were screened and included in the study, wherein 73 cases from Sun Yat-sen University Cancer Center, 27 cases from Nanfang Hospital of Southern Medical University, 26 cases from The First Affiliated Hospital of Sun Yat-sen University, 15 cases from Guangdong General Hospital and 15 cases from Sun Yat-sen Memorial Hospital of Sun Yat-sen University. The overall survival rate was calculated by using Kaplan-Meier method. The prognostic factor was analyzed using the Cox proportional hazards model.

RESULTSIn 156 NEC patients, the ratio of male to female was 3.9 vs 1.0, the median age was 61 years old, and the maximal tumor diameter was (4.5±2.3) cm. There were 12 case(7.7%) with functional tumors. At the initial diagnosis, there were 111 patients (71.2%) with regional lymph node metastases and 58 patients (37.2%) with distant metastases. One hundred and twenty-three patients (78.8%) underwent surgical treatment and 94 patients (60.3%) received systematic treatment. There were 31 patients(19.9%) in localized disease stage, 67 patients (42.9%) in regional disease stage and 58 patients(37.2%) in distant disease stage. The 5-year overall survival rate was 44.7%. Cox regression model showed that surgical treatment (HR=0.512, 95%CI:0.287 to 0.912, P=0.023) and clinical stage(HR=1.488, 95%CI:1.067 to 2.076, P=0.019) were independent prognostic factors. The 5-year overall survival rate of patients with and without surgical treatment were 54.6% and 10.9%(P=0.000). Meanwhile, the 5-year overall survival for localized, regional and distant disease stages were 66.1%, 56.1% and 21.1% respectively(P=0.000).

CONCLUSIONSGastric neuroendocrine carcinoma is a group of rare tumors with strong invasiveness, high malignancy and poor prognosis. The gastric NEC patients can benefit from surgical treatment.