Article: CA-125

CA-125, which stands for cancer antigen 125, is a tumor marker or biomarker that may be elevated in the blood of some people certain cancers. CA-125, a product of the MUC16 gene, and is most commonly thought of as being a marker for ovarian cancer, but it may also be elevated in other cancers, such as endometrial cancer, cancer of the fallopian tubes, lung cancer, breast cancer, and cancer of the gastrointestinal tract. It may also be elevated with a number of benign conditions, such as endometriosis, several benign diseases of the ovary, and may also be elevated during pregnancy. Thus, CA-125 is not perfectly specific for cancer nor is it perfectly sensitive since not every cancer will have an elevated CA-125.

CA-125 is clinically approved for following the response to treatment and predicting prognosis after treatment, especially for ovarian cancer. Its role for early detection of ovarian cancer is controversial and has not yet been adopted for widespread screening efforts in asymptomatic women. The key problem for using it for early detection is that due to its lack of specificity it may lead too many women without cancer to undergo surgery, and CA-125 has not been shown to elevate early enough in the disease process to justify its use for early intervention.

See also

• CA-125 blood test urban legend