The Diagnostic Efficacy Of Stool SDC2 Methylation Test In Colorectal Cancer

Objective:Colorectal cancer(CRC)is one of the most common malignant tumors with high incidence and mortality.Recent studies have shown that a new non-invasive fecal SDC2 methylation test(SDC2)performs well in colorectal cancer screening.This study aims to evaluate diagnostic efficiency of the fecal SDC2 methylation test,quantitative fecal immunochemistry test(q FIT),and serum carcinoembryonic antigen(CEA)for CRC screening.Methods:The study enrolled 135 participants who were admitted to the Second Affiliated Hospital of Nanchang University from August 2019 to December 2021.According to colonoscopy and pathological results,they were divided into four groups,namely CRC,advanced adenoma(AA),AHP(adenomas <1cm and hyperplastic polyps),and normal group.All subjects have undergone colonoscopies,SDC2,q FIT,and CAE.In this study,we not only analyzed the sensitivity and specificity of three indicators,but also plotted the subject receiver operating characteristic curve to evaluate the diagnostic value.In addition,a correlation analysis was performed to explore the potential associations between SDC2 and q FIT and clinical characteristics of CRC patients.Results:The sensitivity of the SDC2 in detecting CRC was 89.47%,significantly higher than that of q FIT(57.89%)and CEA(36.84%).The SDC2 was also especially robust for early-stage CRC(stage I/II),with a sensitivity of 85.71%,q FIT was 42.86%,but the sensitivity of q FIT and CEA were only 42.86% and 19.05%.In addition,the SDC2 outperformed other indices for detecting high-grade intraepithelial neoplasia or AA.In addition,SDC2 has the ability to screen for high-grade intraepithelial neoplasia or AA,better than q FIT and CEA.Even though the specificity of the SDC2 was not the highest,it was still up to 90%(39/43).The diagnostic ability of SDC2 was better than that of q FIT and CEA.Multiple tumor markers have higher diagnostic value for CRC.Surprisingly,we found that the q FIT results are related to the tumor location,size,differentiation,and the grade of CRC,but the SDC2 does not.Conclusion:Fecal SDC2 methylation test has high sensitivity and specificity in CRC,and more sensitive to detected early CRC and AA than q FIT and CEA.Therefore,stool SDC2 methylation test is a better early screening method for CRC.The combination of multiple indicators can further improve the diagnosis rate of colorectal cancer and reduce the rate of missed diagnosis.