CA-15-3 | Breast Cancer Marker

CA 15-3 is a tumor marker most commonly used to monitor the course of breast cancer, especially in treating patients with metastatic or recurrent breast cancer. Although it is not a suitable test for primary breast cancer detection, it is widely applied to evaluate treatment efficacy and early detection of recurrences after stage II or III cancer treatment.

Elevated CA 15-3 concentration is most commonly associated with the progression or metastasis of breast cancer (especially in the bones or liver). However, the amount of this marker can also increase in the presence of certain other malignant tumors (e.g., lung, pancreas, ovary) or benign conditions (e.g., liver cirrhosis, endometriosis, benign breast disease).

Test principle: CA 15-3 concentration is determined by an immunochemical method from venous blood. The results are presented in units of IU/ml. The test is most often evaluated dynamically, observing its changes during treatment.

Recommendations:

• Recommended for patients diagnosed with stage II or III breast cancer after treatment.
• Useful in assessing the effectiveness of treatment for metastatic breast cancer.
• Assigned for long-term disease monitoring to timely detect recurrence.
• Performed together with other tests (e.g., imaging, biopsy), as CA 15-3 alone is not specific for diagnosis.
• Benign conditions may also affect test results, so evaluation along with clinical data is important.
• It is recommended to come for the test fasting for at least 12 hours.