Home / Blood Tests / Cancer Antigen 15.3 (CA 15.3)

Cancer Antigen 15.3 (CA 15.3)

Cancer Antigen 15.3 (CA 15.3) is a tumor marker that is sometimes used in cancer diagnosis and monitoring. It is a protein that is found on the surface of some cancer cells, particularly those of the breast. Elevated levels of CA 15.3 in the blood may indicate the presence of breast cancer, but the test is not specific to breast cancer and false positives can occur. Therefore, CA 15.3 is typically used in combination with other diagnostic tests, such as imaging studies and biopsies, to help diagnose and monitor breast cancer. CA 15.3 levels may also be used to monitor response to treatment and to detect breast cancer recurrence. However, it is important to note that CA 15.3 levels may not always correlate with disease progression or response to treatment, and changes in CA 15.3 levels may also be seen in non-cancerous conditions.

There is an additional £20 phlebotomy fee for every donation.