Gallstone, cholecystectomy and risk of gastric cancer

BACKGROUNDS/AIMS The aim of this retrospective study is to compare stomach cancer incidence, characteristics between gallstones, cholecystectomy and control groups. It also aims to investigate key variables' potential effects on overall survival. METHODS A total of 99 patients, diagnosed with stomach cancers between April 1994 and December 2015, were identified. We excluded stomach cancer patients, accrued during the first year of follow-up in both the gallstones and cholecystectomy groups, assuming that they missed cancers. The main analyses addressing the objective were a chi-square analysis and a survival analysis. RESULTS The incidence of stomach cancers was increased in both the gallstone and cholecystectomy groups, compared with the control group (p=0.003). Multivariate regression analysis showed that the overall survival in gallstones, cholecystectomy group patients as compared with those in the control group decreased (HR=6.66, 95 CI: 1.94-22.80, p=0.003). Also, T-stage was found to statistically affect the rate of overall survival (HR=9.85, 95% CI: 3.09-31.39, p=.000). The stomach cancer showed the worse survival at the posterior, greater curvature location than anterior, lesser curvature of the stomach. (HR=0.30, 95% CI: 0.11-0.80, p=0.017). CONCLUSIONS We provided an awareness of the possible increased risks of stomach cancer in gallstone and cholecystectomy group patients, which might be induced by duodenogastric bile reflux. Also, the survival rate was poor (p<0.000). Therefore, close follow-up strategies for early detection are recommended for such patients.