CA-125 (cancer antigen 125)

CA-125 (cancer antigen 125) is a protein found on the surface of certain cells, particularly those lining the abdomen and pelvis. Elevated levels of CA-125 in the blood can be associated with ovarian cancer, but also with other conditions like benign ovarian cysts, endometriosis, or inflammation. The CA-125 test is mainly used to monitor treatment response in ovarian cancer patients or to help in the diagnosis when combined with other tests. It’s not a definitive test for cancer, as levels can be raised in non-cancerous conditions.