Diagnostic accuracy of DNA-based SDC2 methylation test in colorectal cancer screening: a meta-analysis

Background A growing body of research suggests that methylated genes can be used as early diagnostic markers for cancer. Some studies on methylated Syndecan 2 (SDC2) have shown that it has a great diagnostic ability in colorectal cancer. This meta-analysis was aimed to estimate the diagnostic performance of methylated SDC2 as a potential novel biomarker to screen for the colorectal cancer. Methods Two independent researchers conducted a comprehensive literature search to identify all relevant studies on SDC2 methylation for the diagnosis of colorectal cancer from inception to March 1, 2021. By using STATA and Revman software, the data were analyzed using a Bivariate mixed model. The quality of each study was also evaluated. Results A total of 12 studies comprised of 1574 colorectal cancer patients and 1945 healthy people were included in our meta-analysis. Bivariate analysis showed a pooled sensitivity of 0.81 [95% confidence interval (CI) 0.74-0.86], specificity of 0.95 (95% CI 0.93-0.96), positive likelihood ratio of 15.29 (95% CI 10.83-21.60), and negative likelihood ratio of 0.21 (95% CI 0.15-0.27). The diagnostic odds ratio and the area under the summary ROC curve for diagnosing colorectal cancer were 74.42 (95% CI45.44-121.89) and 0.96 (95% CI 0.94-0.97), respectively. For adenomas, the pooled sensitivity and specificity were 0.47 (95% CI 0.34-0.61) and 0.95 (95% CI 0.92-0.97), respectively. Conclusions Our analysis revealed that methylated SDC2 could be considered as a potential novel biomarker to screen for colorectal cancer. Keywords: Colorectal cancer, SDC2, Meta-analysis