Abstract:
Objective To explore the metastasis rate of gastric neuroendocrine tumors (G-NETs) patients in stage T1~2 and its related risk factors, and to compare the long-term survival results of patients after endoscopic therapy (ET) and surgical treatment.
Methods The data in SEER database were analyzed, and 1 258 patients with pathologically diagnosed G-NETs from January 1, 2004 to December 31, 2015 were included. Logistic regression was used to analyze the influencing factors of metastasis of patients with G-NETs. In patients with T1~2N0M0 stage G-NETs, the general clinical characteristics of patients receiving ET or surgery were compared after propensity matching analysis. The difference of 5-year overall survival (OS) and the risk factors affecting OS between the surgery and ET groups were analyzed by Kaplan-Meier survival curve and Cox proportional hazard regression model.
Results A total of 851 patients with T1 and T2 G-NETs were followed up for 5 years. Lymph node or distant metastasis occurred in 183 patients (21.5%). The metastasis rates of T1 and T2 G-NETs patients were 14.6% and 33.3%, respectively (P < 0.05). Multivariate logistic regression analysis showed that tumor grade G3/4, invasion of lamina propria and tumor diameter > 20 mm were closely related to metastasis of T1~2 stage G-NETs. The 5-year survival rate of patients in non-metastasis group (n=668) was 85.1%, and that of patients in metastasis group (n=183) was 34.7% (P < 0.05). Subgroup analysis showed that during the 5-year follow-up, the average survival time of patients with metastasis after surgery and ET treatment was 42.0 months and 31.3 months (χ2=14.510, P < 0.05), and the average survival time of patients without metastasis after surgery and ET treatment was 53.2 months and 52.3 months (χ2=0.279, P=0.598). After propensity matching analysis, the 5-year survival rate of patients with T1~2N0M0 G-NETs was similar after ET and surgery (88.8% vs 89.4%, χ2=0.22, P=0.882). Multivariate Cox proportional hazard regression model showed that age, histological grade and depth of invasion were related to OS of patients with T1~2N0M0 G-NETs.
Conclusions The tumor grade G3/4, invasion of lamina propria and tumor diameter > 20 mmmight be closely related to the metastasis of G-NET in T1~2 stage, the prognosis of these patients with metastasis is poor. 5-year survival rate in patients with T1~2N0M0 G-NETs are similar after ET and surgery.