Aberrant methylation of genes in stool samples as diagnostic biomarkers for colorectal cancer or adenomas: a meta-analysis

Background: An increasing number of hypermethylated genes in stool samples have been reported as biomarkers for the detection of colorectal cancer (CRC) or adenomas. We aimed to comprehensively review and compare the evidence for feasibility of using these biomarkers for the detection of colorectal neoplasia. Methods: We searched Medline, the Web of Science and OVID for studies that used hypermethylated genes as biomarkers for the detection of CRC or adenomas. A meta‐analysis was carried out using the random‐effect model with diagnostic odd ratios (DOR) and 95% confidence intervals (CI) as effect measurements. Results: A total of 19 studies including 2,356 patients were eligible for final analysis. The sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and DOR for the detection of CRC or adenomas were 0.62 (95% CI: 0.51–0.71), 0.89 (95% CI: 0.86–0.92), 5.66 (95% CI: 4.68–6.83), 0.43 (95% CI: 0.34–0.55) and 13.15 (95% CI: 9.82–17.60) respectively. Of these, the sensitivity and specificity for the detection of adenoma were 0.54 (95% CI: 0.39–0.68) and 0.88 (95% CI: 0.83–0.92) respectively. Conclusions: Hypermethylated gene panels are not currently accurate enough to be used alone for colorectal neoplasia screening. The discovery and evaluation of additional biomarkers with improved sensitivity and specificity is necessary.