Incidence and risk of remnant gastric cancer after gastrectomy for gastric cancer: a population-based study from the SEER database

Abstract

Abstract Background Gastric cancer (GC) constitutes a major global health problem, of which remnant gastric cancer (RGC) occurs less frequently. The rate of RGCs after gastrectomy for GC is increasing recently due to improved survival and screening, however, their incidence and risk have not been reported in the U.S. population. The objective of this study was to evaluate the incidence and elevated risk of RGC after GC gastrectomy in this population, and to identify the risk factors. Methods Patients underwent gastrectomy for first primary GC in 2000–2015 and those who developed RGC were identified from Surveillance, Epidemiology and End Results (SEER) database. Fine-Gray regression was used to estimate the cumulative incidence and to identify risk factors. Standardized incidence ratios (SIRs) were calculated by Poisson regression to compare the risk with the general population. Results Among 21,566 patients included in the cohort, 227 developed RGC. The 20-year cumulative incidence of RGC was 1.88%. Multivariate analysis revealed that older age, invasion depth, male sex, marital status, and lower income are independent risk factors for RGC development. SIR was 7.70 overall and > 4.5 in each stratum. Conclusions Cumulative incidence and risk for RGCs increased continuously in patients underwent GC gastrectomy. Close and lifelong endoscopy surveillance should be recommended for patients who received GC gastrectomy, especially those with high-risk factors.