I am assuming you're referring to a blood test called the CA-125. It is not possible to interpret the meaning of an abnormally high CA 125 without additional information about the particular patient being evaluated. The reason is that this protein can be increased in many different benign and malignant conditions. The two most frequent situations in which CA 125 is used is to monitor patients with a known cancer or as one of several tests in the workup of a patient suspected of having a tumor.
The most common use of the test is the monitoring of women with known ovarian cancer. A decreasing level generally indicates that therapy, including chemotherapy, has been effective, while an increasing level indicates tumor recurrence. Because of test variation, small changes are usually not considered significant. A doubling or halving of the previous value would be important.
In the patient who is being evaluated for a pelvic mass, a CA 125 level greater than 65 is associated with malignancy in approximately 90% of cases. However, without a demonstrable mass, the association is much weaker.
A number of benign conditions can cause elevations of the CA 125 level, including pregnancy, endometriosis, uterine fibroids (benign tumors), pancreatitis, normal menstruation, pelvic inflammatory disease, and liver disease. Benign tumors of the ovaries can also cause an abnormal test result. Increases can also be seen in cancers other than ovarian cancer, including malignancies of the uterine tubes, endometrium, lung, breast, and gastrointestinal tract.