Today, only carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 19‐9, cancer antigen (CA) 125 and prostate‐specific antigen (PSA) are used routinely in daily clinical practice in the management of patients with known cancer, but their sensitivity and specificity are too low to be used in screening of patients suspected of having cancer.3, 4, 5, 6, 7, 8, 9. The gene discussed is CEACAM5; the disease is cancer.