Serum CA 15-3 antigen measurement is used to manage breast cancer patients in combination with clinical information and other diagnostic tests to detect early relapse in patients who have previously been treated for breast cancer and to monitor response to treatment in patients with metastatic breast cancer.
Cancer markers are substances produced by cells of the body in response to the presence of tumors. Cancer Antigen 15-3 (CA 15-3) is a glycoprotein found in benign and malignant breast disease, as well as in breast cancer with liver or bone metastases. The highest cancer antigen 15-3 levels were found in metastatic breast cancer. Screening for CA 15-3 is useful in the diagnosis of metastatic breast cancer and in monitoring the response of patients to breast cancer treatment. As CA 15-3 levels may not be elevated in the early stages of breast malignancy, screening for CA 15-3 is not useful as a screening test.
Elevated levels of CA 15-3 have also been found in patients without cancer and in patients with other forms of cancer, such as liver, lung, and ovarian cancer. The higher the value of cancer antigen 15-3, the more advanced the breast cancer and the greater the chance of metastasis. Mild to moderate increase in CA 15-3 may also be found in certain non-cancerous conditions, such as in liver cirrhosis. CA 15-3 levels in non-cancerous conditions tend to remain constant over time, whereas in metastatic breast cancer levels continue to increase.
Possible Interpretations of Pathological Values
- Increase: Breast cancer, chronic hepatitis, cirrhosis, colorectal cancer, fibrocystic breast disease, liver cancer, lung cancer, metastatic breast cancer, ovarian cancer, pancreatic cancer, sarcoidosis, systemic lupus erythematosus.
Laboratory test results are the most important parameter for the diagnosis and monitoring of all pathological conditions. 70%-80% of diagnostic decisions are based on laboratory tests. The correct interpretation of laboratory results allows a doctor to distinguish "healthy" from "diseased".
Laboratory test results should not be interpreted from the numerical result of a single analysis. Test results should be interpreted in relation to each individual case and family history, clinical findings, and the results of other laboratory tests and information. Your personal physician should explain the importance of your test results.
At Diagnostiki Athinon we answer any questions you may have about the test you perform in our laboratory and we contact your doctor to get the best possible medical care.