In addition, various non-invasive methods have been utilized for early CRC screening, including the FIT, the multi-target fecal DNA (MT-sDNA) test, the plasma DNA methylated septin 9 (SEPT9) test, the fecal DNA methylated syndecan 2 (SDC2) test, etc., but these methods usually suffer from low sensitivity and specificity for early-stage CRC and precancerous lesions [5,6]. This evidence concerns the gene SDC2 and colorectal carcinoma.