Detection of Fusobacterium nucleatum in feces and colorectal mucosa as a risk factor for colorectal cancer : a systematic review and meta-analysis

Abstract

Background: Colorectal cancer (CRC) is a major cause of cancer deaths worldwide. Accumulating evidence suggests a potentially important role of colorectal infection with Fusobacterium nucleatum (F. nucleatum) in colorectal carcinogenesis. We conducted a systematic review, including both a qualitative synthesis and a metaanalysis, to synthesize the evidence from the epidemiological literature on the association between F. nucleatum detection in the colon/rectum and CRC. Methods: A systematic literature search of Ovid MEDLINE(R), Embase, Web of Science Core Collection, EBM Reviews—Cochrane Database of Systematic Reviews, and CINAHL Plus with Full Text was conducted using earliest inclusive dates up to 4 October 2020. Eligible studies were original, comparative observational studies that reported results on colorectal F. nucleatum detection and CRC. Two independent reviewers extracted the relevant information. Odds ratio (OR) estimates were pooled across studies using the random effects model. NewcastleOttawa scale was used to critically appraise study quality. Results: Twenty-four studies were included in the systematic review, of which 12 were included in the metaanalysis. Studies investigated F. nucleatum in feces, colorectal tissue samples, or both. In most studies included in the systematic review, the load of F. nucleatum was higher, on average, in specimens from CRC patients than in those from CRC-free controls. Meta-analysis showed a positive association between F. nucleatum detection in colorectal specimens and CRC (OR = 8.3; 95% confidence interval (95% CI) 5.2 to 13.0). Conclusions: The results of this systematic review suggest that F. nucleatum in the colon/rectum is associated with CRC.