For the basic performance test of the CORD assay to detect hypermethylated cancer-derived DNA against a background of blood-derived DNA, we spiked DNA from colon cancer cell line HCT116 (control DNA for methylation of TWIST1 and SEPT9) at ratios of 100%, 50%, 10%, 5%, 1.1%, 0.11%, and 0% into DNA extracted from leukocyte DNA (control DNA for unmethylation of TWIST1 and SEPT9) and measured the methylation levels of TWIST1 and SEPT9 for each sample. This evidence concerns the gene TWIST1 and malignant colon neoplasm.