What does an elevated CA 125 mean, and how is the test used?
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 blood levels of 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 (malignancy) 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 cancer of the ovary (ovarian cancer). In the patient who is known to have a malignancy, such as ovarian cancer, the CA 125 level can be monitored periodically. 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 patie
