cancer antigen

Abbreviation: CA
A protein or carbohydrate that is either expressed by cancerous cells but not by healthy cells or is expressed by cancerous cells in much greater concentrations than by healthy cells. Cancer antigens are used in clinical medicine to screen body fluids for tumors or to follow the response of tumors to treatment. Since they stimulate the immune response, they are also used in the manufacture of antitumor vaccines. See: table Note: several antigens on this list also detect benign diseases and conditions.

Antigen name or designation	Abbreviation	The tumor it detects
Alpha-fetoprotein	AFP	Nonseminomatous germ cell tumor
CA 15–3		Breast cancer
CA 19–9		Pancreatic cancer
CA 50		Gastrointestinal tract tumors
CA 125		Ovarian/peritoneal cancer
Carcinoembryonic antigen	CEA	Gastrointestinal tract tumors and tumors of solid internal organs
Human chorionic gonadotropin	HCG	Nonseminomatous germ cell tumors; choriocarcinoma
Microglobulin-beta 2 subunit	b2–M	Multiple myeloma
Neuron-specific enolase	NSE	Broad variety of cancers, including small cell carcinoma of lung
NY-BR-40 and others		Breast cancer
Prostate specific antigen	PSA	Prostate cancer
Urinary tumor associated antigen	UTAA	Melanoma