Cancer Antigen (CA) 125, Serum
Fasting Required: No

Specimen: Blood

Lab: Quest Diagnostics

Results: 3-5 business days

Note: Result turnaround times are an estimate and are not guaranteed. Our reference lab may need additional time due to weather, holidays, confirmation/repeat testing, or equipment maintenance.

Limitations: CA 125 is not intended as a screening test. CA 125 is affected by menstrual cycle, ectopic endometrial tissue.

Description: CA-125 is a protein present on the surface of most ovarian cancer cells. Testing for CA-125 is used to monitor treatment or detect recurrence of ovarian cancer. It is not typically used as a general screening test because levels can be elevated in other conditions such as normal menstruation, pregnancy, endometriosis, and pelvic inflammatory disease. CA 125 can also be detected in other cancers such as pancreas, liver, colon, breast, endometrial, fallopian tube, gastrointestinal, and lung.

The CA 125 level can provide prognostic information in the follow-up management of patients with ovarian carcinoma. The assay should be used as an adjunctive test in the management of ovarian cancer patients. CA 125 is not recommended as a cancer screening procedure to detect cancer in the general population.

Alternative Name(s): OC125, Cancer Antigen 125, Ovarian Antigen