Application of human stool SDC2 methylation for early screening of colorectal cancer

LI Na; XU Ye; SHI Qianfei; YUAN Hang; WU Wen

Abstract：Objective:To investigate the clinical value of human stool SDC2 methylation in the early noninvasive de-tection of colorectal cancer(CRC).Methods:A total of 60 CRC patients treated at Yichun People's Hospital from Au-gust 2022 to December 2023 were enrolled in CRC group,and 60 healthy people who underwent physical examination in hospital during the same period were enrolled in the healthy group.The methylation level of stool SDC2 gene was ana-lyzed by fluorescent quantitative polymerase chain reaction(PCR)technique,and the concentrations of serum tumor markers carcinoembryonic antigen(CEA)and carbohydrate antigen 19-9(CA19-9)were detected by chemilumines-cence method.The diagnostic value of stool SDC2 methylation and serum tumor markers for CRC were compared.Re-ceiver operating characteristic(ROC)curves were used to evaluate the area under the curve(AUC)for CRC diagnosis.Results:Statistical analysis showed the level of stool SDC2 methylation was significantly higher in the CRC group than in the healthy group(P＜0.05).The positive rates of SDC2methylation,CEA and CA19-9 in CRC group were signifi-cantly higherin the CRC group compared to the healthy group(P＜0.05).In CRC group,the positive detection rates of SDC2 methylation,CEA and CA19-9 were 81.7％,43.3％and 40.0％,respectively,indicating a higher true positive rate for SDC2 methylation compared to serum tumor markers.ROC curve analysis revealed that stool SDC2 methylation detection had an AUC of 0.896 8,which was higher than that of combined CEA/CA19-9 detection(AUC=0.8297).Notably,the highest AUC value was observed with combined SDC2/CEA/CA19-9 detection at 0.934 7.The sensitivity and specificity of SDC2 methylation,CEA,CA1 9-9 and SDC2/CEA/CA19-9 combined detection were 83.3％,71.7％,50.0％and 88.3％,respectively,the specificity was 83.3％,85.0％,85.0％and 88.3％respectively,which indicated that the com-bined diagnosis model had the highest sensitivity and specificity.Conclusion:The stool SDC2 gene detection exhibited a high level of sensitivity and specificity for CRC;however,the combined diagnostic model ofSDC2/CEA/CA19-9 dem-onstrated superior screening efficacy for early CRC.