However, low sensitivity and low specificity for early-stage CRC detection using conventional screening methods such as the fecal occult blood test (FOBT) and fecal immunochemical test (FIT) [4,5], stool molecular tests [8,9], the blood-based carcinoembryonic antigen (CEA) [10] and SEPT9 tests [11] are still a major concern. The gene discussed is CEACAM5; the disease is colorectal carcinoma.