- CA-125 is a Tumor Marker used to monitor therapy during treatment for ovarian cancer. CA-125 is also used to detect whether cancer has come back after treatment is complete. This test is sometimes used to follow high-risk women who have a family history of ovarian cancer but who do not yet have the disease.
- If CA-125 levels fall during therapy, this generally indicates that the cancer is responding to treatment. If CA-125 levels rise, the cancer may not be responding to therapy. High CA-125 levels after treatment is complete may indicate that the cancer has come back.