Metformin and colorectal cancer: a systematic review, meta-analysis and meta-regression.

Purpose: Metformin may have a role in reducing the incidence of colorectal cancer (CRC) and improving survival outcome. This meta-analysis explored the effect of metformin use on colorectal adenoma and cancer incidence, and colorectal oncological outcomes.

Methods: A database search was conducted on Medline, Embase and CNKI for studies comparing metformin vs.