The association between cholecystectomy and the risk of colorectal cancer: an updated systematic review and meta-analysis of cohort studies.

BACKGROUND

The effect of cholecystectomy on the development of colorectal cancer (CRC) has prompted a large number of population-based studies. However, the results of these studies are debatable and inconclusive. Our aim in the present study was to conduct an updated systematic review and meta-analysis to explore the causality between cholecystectomy and CRC.

METHODS

Cohort studies published in the PubMed, Web of Science, Embase, Medline, and Cochrane databases up to May 2022 were retrieved. Pooled relative risks (RRs) and 95% confidence intervals (CIs) were analyzed using a random effects model.

RESULTS

Eighteen studies, involving 1,469,880 cholecystectomy and 2,356,238 non-cholecystectomy cases, were eligible for the final analysis. Cholecystectomy was not associated with the development of CRC (P=0.109), colon cancer (P=0.112), or rectal cancer (P=0.184). Subgroup analysis of sex, lag period, geographic region, and study quality revealed no significant differences in the relationship between cholecystectomy and CRC. Interestingly, cholecystectomy was significantly associated with right-sided colon cancer (RR =1.20, 95% CI: 1.04-1.38; P=0.010), especially in the cecum, the ascending colon and/or the hepatic flexure (RR =1.21, 95% CI: 1.05-1.40; P=0.007) but not in the transverse, descending, or sigmoid colon.

CONCLUSIONS

Cholecystectomy has no effect on the risk of CRC overall, but a harmful effect on the risk of right-sided colon cancer proximally.