We firstly demonstrated that there was a subsite difference in colorectal methylation between TFPI2 and SDC2, and as high as 88.0% SDC2 hypomethylated CRC samples retrieved from TCGA were TFPI2 hypermethylated (Table 2), in agreement with the result from the MSP assays in stool samples (Table 3). Here, TFPI2 is linked to colorectal carcinoma.