Results of the CA 125 test are measured in units per milliliter (U/mL). The normal value is less than 35 U/mL.
If your CA 125 level is higher than normal, you may have a benign condition, or the test result could mean that you have ovarian, endometrial, peritoneal or fallopian tube cancer. Your doctor may recommend other tests and procedures to determine your diagnosis.
If you've been diagnosed with ovarian, endometrial, peritoneal or fallopian tube cancer, a decreasing CA 125 level often indicates that the cancer is responding to treatment. A rising CA 125 level may indicate a return or continued growth of the cancer.
A number of normal and noncancerous conditions can cause an elevated CA 125 level, including:
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- Liver disease
- Pelvic inflammatory disease
- Uterine fibroids
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- Tumor markers: Questions and answers. National Cancer Institute. http://www.cancer.gov/cancertopics/factsheet/detection/tumor-markers. Accessed Dec. 10, 2013.
- Cancer antigen 125 (CA 125), serum. Mayo Medical Laboratories. http://www.mayomedicallaboratories.com/test-catalog/Clinical+and+Interpretive/9289. Accessed Dec. 11, 2013.
- Moyer VA, et al. Screening for ovarian cancer: U.S. Preventive Services Task Force reaffirmation recommendation statement. Annals of Internal Medicine. 2012;157:900.
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