Overview: Cancer Antigen 15-3 TestIntroduction: The Cancer Antigen 15-3 Test measures CA 15-3, a cancer marker to monitor breast cancer, causing breast lumps or pain. Following 2023 NCCN guidelines, it uses an immunoassay for high sensitivity, aiding in cancer screening. This test is critical for guiding treatment monitoring, assessing disease progression, and improving outcomes in immunology for patients with suspected breast cancer.
Other Names: CA 15-3 Assay, Breast Cancer Marker Test.
FDA Status: Laboratory-developed test (LDT), meeting immunology standards for diagnostic accuracy.
Historical Milestone: CA 15-3 testing began in the 1980s with breast cancer research. Immunoassays emerged in the 1990s, and by the 2000s, high-sensitivity assays improved monitoring accuracy.
Purpose: Monitors breast cancer, guides treatment, and assesses disease progression in patients with breast lumps or pain.
Test Parameters: 1. CA 15-3
Pretest Condition: No fasting required. Collect serum at any time. Report symptoms like breast lumps or pain, and list medications like chemotherapy.
Specimen: 2-5 mL serum (SST). Centrifuge within 1 hour. Transport in a biohazard bag within 8 hours.
Sample Stability at Room Temperature: 8 hours
Sample Stability at Refrigeration: 7 days
Sample Stability at Frozen: 6 months
Medical History: Document breast lumps, pain, or family history of breast cancer. Include current medications, especially chemotherapy or targeted therapies.
Consent: Written consent required, detailing the tests purpose, diagnostic implications, and potential need for cancer treatment.
Procedural Considerations: Uses an immunoassay to measure CA 15-3 levels. Results are available in 1-2 days, enabling rapid clinical decisions.
Factors Affecting Result Accuracy: Benign breast conditions or liver disease may elevate CA 15-3 levels. Hemolysis or improper storage can degrade samples.
Clinical Significance: Elevated CA 15-3 levels indicate breast cancer progression, prompting chemotherapy or surgery. Normal levels suggest stable disease or remission.
Specialist Consultation: Consult an oncologist for result interpretation. A breast surgeon referral is advised for advanced cases.
Additional Supporting Tests: Mammogram, breast MRI, or CA 27-29 test to confirm breast cancer or assess disease extent.
Test Limitations: False positives may occur with benign conditions. Results require clinical correlation with imaging.
References: NCCN Breast Cancer Guidelines, 2023; Journal of Clinical Oncology, Harris L, 2022.
