in the Colorectum and Its Association with Cancer Risk and Survival: A Systematic Review and Meta-analysis.

Background: The gut microbiome, in particular , has been reported to play a role in colorectal cancer development and in patient prognosis. We aimed to perform a systematic review and meta-analysis of published studies to assess the prevalence of in colorectal tumors and evaluate the association between and colorectal cancer development and prognosis.

Methods: MEDLINE, EMBASE, and Web of Science databases were systematically searched for studies published until January 2019.