In addition to DTC, studies indicate that MK can outperform several currently used blood tumor specific biomarkers, such as alpha fetoprotein (AFP) for hepatocellular carcinoma (HC)32, 33, carcinoembryonic antigen for colorectal cancer34, carcinoembryonic antigen and cytokeratin 19 fragments for esophageal squamous cell carcinoma35. The gene discussed is CEACAM5; the disease is neoplasm.