Description:

Cancer antigen 125 (CA-125) measure the amount of this protein in the blood. CA-125 is found on the surface of many ovarian cancer cells. It also can be found in other cancers and in small amounts in normal tissue.

CA-125 is used as a tumor marker-which means some types of cancer are present. Most often, the CA-125 test is used to check how well treatment for ovarian cancer is working or to see if ovarian cancer has returned.

The test for cancer antigen 125 (CA-125) is used to:check if treatment for cancer is working. If the level of CA-125 is going down, it usually means that the treatment is working; check if cancer has returned; check if the ovary is the main site of cancer in a woman. If a cancer is found at another site (metastatic cancer), a higher-than-normal CA-125 test result may mean that ovarian cancer is the main site.

The CA-125 test is not recommended as a screening test for ovarian cancer at this time. However, the CA-125 test and ultrasound may be used to test women who have a high chance for ovarian cancer. This would be women who have a family history of ovarian cancer that is likely to be inherited.

  Noncancerous conditions with high values:Some noncancerous conditions may cause high levels of CA-125. These conditions include pelvic inflammatory disease (PID), endometriosis, uterine fibroids, liver disease (such as hepatitis or cirrhosis), pancreatitis, the first trimester of pregnancy, the menstrual cycle, and lupus.

   Cancerous conditions with high values :Ovarian cancer or cancer in the fallopian tubes or the endometrium can cause high levels of CA-125;Other types of cancer also may cause a high CA-125 level. These include cancer of the pancreas, stomach, esophagus, liver, breast, colon, or lung;Most women with an ovarian cancer lump that can be felt in the pelvic area have CA-125 values greater than 65 U/mL.