A CA 125 test measures the amount of the protein CA 125(cancer antigen 125) in your blood. A CA 125 test may be used to monitor certain cancers during and after treatment. In some cases, a CA 125 test may be used to look for early signs of ovarian cancer in people with a very high risk of the disease.
What is the normal range for a CA 125 test?
CA 125 is the only tumor marker recommended for clinical use in the diagnosis and management of ovarian cancer. The reference range of CA 125 is 0-35 units/mL (0-35 kU/L). The cutoff of 35 kU/L for CA 125 was determined from the distribution of values in healthy individuals to include 99% of the normal population.