Risk factors for metachronous colorectal cancer or polyp: A systematic review and meta-analysis

Abstract

Background and Aim: We conducted a systematic review and meta-analysis to identify personal, lifestyle, and tumor-related risk factors for metachronous colorectal cancer (CRC) and polyp. Methods: Relevant studies were identified by searching MEDLINE, Web of Science and Cochrane Central Register through 15 May 2016. Estimates for associations were summarized using random effects models. Results: Fifty-five studies were included in the review. For individuals who had a CRC resection, having a synchronous polyp was a risk factor for metachronous CRC or polyp (relative risk [RR], 2.04; 95% confidence interval [CI], 1.48–2.82) and having a synchronous CRC (RR, 1.90; 95% CI, 1.25–2.91) and proxima..