Objective: To analyze the clinicopathologic characteristics of gastroenteropancreatic neuroendocrine neoplasm(GEP-NET) and explore the prognostic factors for patients with GEP-NET.
Methods: Retrospectively reviews were conducted for the charts of 68 patients diagnosed pathologically with GEP-NET and treated at Sichuan Cancer Hospital during January 2001 to June 2012. The information of prognostic factors was retrieved and analyzed. Kaplan-Meier method was used to estimate survival rates and plot patient survival curves of patients at different levels of predictive factors. The association between clinicopathologic characteristic and prognosis in GEP-NET patients was assessed with Log-rank test. Meanwhile Cox proportional hazard model was used to select independent risk factors of patient survival.
Results: Stomach (20/68,29.41%) and cardia (16/68,23.53%) were mostly involved. Frequent tumor sites for males were stomach and cardia (34/52,65.38%) while the most common site was intestinal canal for female (12/16) . Ages of disease onset were different significantly among patient groups of different sites (P = 0.023). The average age of intestinal NET was the highest while gastric NET had the lowest. During a median follow-up duration of 49 (3-120)months, there were 37 deaths (54.41%), including 30 from postoperative relapses. Postoperative survival time ranged from 4-115 months. The mean survival periods were (46 ± 7) months respectively. The 1, 3, and 5-year survival rates were 65.1%, 41.5% and 28.7% respectively. Univariate analyses showed that the risk factors of survival time were patient age over 60 years, tumor size > 2 cm, T2-4 stage of tumor, vascular invasion, lymph node metastasis, distant metastasis, positive surgical margin and pathological grades of neuroendocrine carcinoma (NEC) and mixed adenoneuroendocrine carcinoma (MANEC). Multivariate analysis indicated independent risk factors were tumor size > 2 cm and pathological grades of NEC and MANEC.
Conclusions: GEP-NET may occur at multiple sites of digestive system and lack specific clinical manifestations. Tumor size, distant metastasis and pathological grades were independent prognostic factors for GEP-NET patients.