•To monitor therapy during treatment for ovarian cancer.
•To detect whether cancer has come back after treatment is complete.
•To test and monitor high-risk women who have a family history of ovarian cancer but who do not yet have the disease.
Cancer antigen 125 (CA 125) is a transmembrane glycoprotein that was first identified in human ovarian carcinoma cell lines.CA 125 has been widely used to monitor women with epithelial ovarian cancer.
High CA 125 level has been found in 80% patients with epithelial ovarian cancer and more than 90% patients with advanced ovarian cancer. However, elevated CA 125 may also be found in other cancers, including cervical cancer, breast cancer, primary peritoneal cancer and fallopian tube cancer. The good correlation with response to initial therapy of epithelial ovarian cancer guaranteed the use of CA 125 as a follow-up marker. CA 125 is the best marker used to follow women during or after treatment for epithelial ovarian cancer. Meanwhile, it has been used for the detection of cancers of the cervix or breast, in combination with other tumor markers.
Recurrent ovarian cancer patients who achieved complete clinical response to primary therapy have a significantly higher CA 125 levels than those who did not develop recurrent cancer.