Carcinoembryonic antigen (CEA) is a substance produced during fetal development. Generally, its concentration in the blood decreases after birth.
In oncology, CEA can be used as a tumor marker for the presence and activity of certain types of tumors in adults and children. Among the tumors that may have elevated CEA levels are those of the gastrointestinal tract, breast cancer, lung cancer, pancreatic cancer, ovarian cancer, and central nervous system cancer.
Carcinoembryonic antigen, serum (CEA) can also be present in some benign conditions. Additionally, smokers may have CEA levels above normal. CEA is most commonly measured in the blood but can also be measured in cerebrospinal fluid.
