Individual test · Labcorp 002303

Cancer Antigen (CA) 125

This test measures the level of CA 125, a protein in your blood that is often found in higher amounts in women with ovarian cancer. It is primarily used to monitor how well cancer treatment is working or to check if the cancer has returned after therapy. While high levels can suggest a problem, this test helps doctors evaluate pelvic masses alongside other exams. However, it cannot diagnose cancer by itself because common non-cancerous conditions, such as endometriosis or fibroids, can also cause high results.