Carcinoembryonic antigen

Carcinoembryonic antigen (CEA) is a protein found in many types of cells but associated with tumors and the developing fetus. CEA is tested in blood. The normal range is Benign conditions that can increase CEA include smoking, infection, inflammatory bowel disease, pancreatitis, cirrhosis of the liver, and some benign tumors (in the same organs which have cancers with increased CEA). Benign disease does not usually cause a CEA increase over 10 ng/ml. The main use of CEA is as a tumor marker, especially with intestinal cancer. The most common cancers that elevate CEA are in the colon and rectum. Others: cancer of the pancreas, stomach, breast, lung, and certain types of thyroid and ovarian cancer. Levels over 20 ng/ml before therapy are associated with cancer which has already metastasized (spread). CEA is useful in monitoring the treatment of CEA-rich tumors. If the CEA is high before treatment, it should fall to normal after successful therapy. A rising CEA level indicates progression or recurrence of the cancer. (Chemotherapy and radiation therapy can themselves cause a rise in CEA due to death of tumor cells and release of CEA into the blood stream but that rise is typically temporary). "Carcinoembryonic" reflects the fact that CEA is made by some cancers ("carcino-") and by the developing fetus ("-embryonic").

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car·ci·no·em·bry·on·ic antigen .kärs-ən-ō-.em-brē-.än-ik- n a glycoprotein present in fetal gut tissues during the first two trimesters of pregnancy and in peripheral blood of patients with some forms of cancer (as of the digestive system or the breast) abbr. CEA

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(CEA) a glycoprotein secreted into the glycocalyx coating the luminal surface of gastrointestinal epithelia. Originally thought to be a specific antigen of the fetal digestive tract and adenocarcinoma of the colon, CEA is now known to occur normally in feces and pancreaticobiliary secretions and to appear in the plasma in a diverse group of neoplastic and non-neoplastic conditions, including cancers of the colon, pancreas, stomach, lung, and breast, alcoholic cirrhosis and pancreatitis, inflammatory bowel disease, rectal polyps, and cigarette smoking. The primary use of CEA is in monitoring response to treatment of colorectal cancer.