Association between history of cholecystectomy and risk of gastric cancer: a meta-analysis of epidemiological studies

PURPOSE: Evidence from previous studies on the association between cholecystectomy and risk of gastric cancer are still inconsistent. We aimed at conducting a meta-analysis of epidemiological studies to evaluate this association. METHODS: Researchers searched three databases (PubMed, Embase and Web of Science) through January 2021 for eligible studies. Relative risks (RRs) and 95% CIs in each included studies were pooled by random-effects models. Patients and the public were not involved in our study. RESULTS: Eight studies were identified. Four studies reported significantly positive association between history of cholecystectomy and risk of gastric cancer, and the remaining studies reported null association. The pooled RR of these eight studies showed that a history of cholecystectomy was associated with a 11% higher risk of gastric cancer (pooled RR=1.11, 95% CI: 1.03 to 1.20). Moderate heterogeneity across the studies was detected (p=0.117, I(2)=37.8%). The pooled RRs were 1.12 (95% CI: 1.01 to 1.24) for five cohort studies and 0.95 (95% CI: 0.66 to 1.38) for three case–control studies. Compared with the risk in Europe and the USA, the pooled RR was higher for two studies conducted in Asia. Six studies were assessed as high-quality studies with the pooled RR of 1.12 (95% CI: 1.02 to 1.23). The pooled results were robust by sensitivity analyses, and no indication of publication bias was detected. CONCLUSION: This meta-analysis suggests that a history of cholecystectomy may be associated with an increased risk of gastric cancer.