Cancer Antigen 125 (CA-125) Test

CA-125 protein

Robert Bast and his laboratory developed an antibody-based test (immunoassay) to detect a protein that can be detected in the serum of human blood. The protein - cancer antigen 125 or CA-125 - is found at increased levels in the blood of some women who have ovarian cancer.1 The test is used to help diagnose some types of ovarian cancers. It is also used to track the progress of treatment and recurrence of the disease.

  • 1Bast, R.C., et al. "A Radioimmunoassay Using a Monoclonal Antibody to Monitor the Course of Epithelial Ovarian Cancer." New England Journal of Medicine. 309 (1983): 883-887. [PUBMED]