# Carcinoembryonic Antigen

National Cancer Institute

## Source

National Cancer Institute. Carcinoembryonic Antigen. NCI Thesaurus. Code C25159.

A cancer-specific antigen associated with both tumors and the developing fetus. The main use of this antigen is as a tumor marker, especially with respect to intestinal cancers. Production of the antigen ceases shortly before birth, but may reappear in people who develop certain types of cancer.