Measuring gut microbiome as a colorectal cancer screening tool: potential and challenges

Introduction: Colorectal cancer (CRC) represents a global public health challenge, ranking as the third most prevalent cancer globally. Population-based screening programs for average-risk populations have proven effective in reducing incidence and mortality of CRC through early detection of cancer. The fecal immunochemical test (FIT), the standard diagnostic method in many nations, still falls short in diagnostic effectiveness, resulting in undetected adenomas and, more significantly, unnecessary colonoscopies. Areas covered: One of the primary research focuses in the field of CRC is the discovery of new, noninvasive biomarkers. Recent studies, including metagenomic meta-analyses, have discovered common microbial signatures able to reproducibly discriminate between patients with CRC and healthy controls. Based on this evidence, international guidelines have recently recommended the use of microbiome-based biomarkers for CRC screening in clinical settings, although such studies have yet to be conducted. Expert opinion: This field of research needs considerable multidisciplinary efforts, including large and geographically different meta-cohorts, and the application of state-of-the-art computational approaches, to identify reproducible signatures able to predict early lesions. Such diagnostic tool would revolutionize CRC screening. More widely, it would provide a mind-set shift in the clinical and scientific community promoting the exploitation of diagnostic and therapeutic microbiome tools in clinical practice.