Quick Facts
- Sample: Blood
- Fasting: No fasting required. Stop biotin consumption at least 72 hours prior to collection.
- Turnaround: 4-6 business days. May take longer based on weather, holiday, or lab delays.
What This Test Measures
This test measures Cancer Antigen 15-3 (CA 15-3), a tumor marker that certain cancer cells produce and release into the bloodstream. Breast cancer is one of the cancers that can release CA 15-3, particularly following treatment. Your body's immune system responds to this substance as part of its defense against cancerous cells.
CA 15-3 is used to monitor the response to invasive breast cancer treatment and to monitor for disease recurrence. It is not used to screen for or diagnose breast cancer. Elevated levels do not necessarily indicate the presence of cancer, since other conditions, such as liver disease or benign breast conditions, can also raise CA 15-3 levels. Because of this, further testing and evaluation are needed to reach a definitive diagnosis.
Benefits
- Tracks CA 15-3 levels during invasive breast cancer treatment.
- Supports monitoring for possible breast cancer recurrence after treatment.
- Provides bloodwork your provider can review alongside other findings.
- Offers a simple blood draw with no fasting required.
- Gives ongoing information to discuss with your healthcare provider.
Who Is This Test For?
- Individuals who have been diagnosed with breast cancer and need treatment monitoring.
- Individuals who have completed breast cancer treatment and need recurrence monitoring.
- Individuals experiencing a lump in the breast.
- Individuals experiencing bloody nipple discharge.
- Individuals noticing changes in the shape or feel of the breast or nipple.
- Individuals with redness or swollen lymph nodes near the breast.
How It Works
- Order Your Test Online
- Visit a Local Lab
- Get Results Online
FAQ
1. What is the purpose of this test?
This test measures Cancer Antigen 15-3 (CA 15-3), a tumor marker released by certain cancer cells, including some breast cancer cells. It is used to monitor the response to invasive breast cancer treatment and to monitor for possible recurrence of the disease. This test is not used to screen for or diagnose breast cancer. An abnormal result does not confirm that cancer is present or has returned, and a normal result does not rule out cancer.
2. Who would benefit from this test, and when should I order it?
This test may be appropriate for individuals who have been diagnosed with breast cancer and need ongoing treatment monitoring, or who have completed breast cancer treatment and need monitoring for possible recurrence. It may also be considered by individuals experiencing symptoms such as a breast lump, bloody nipple discharge, changes in breast or nipple appearance, or swollen lymph nodes near the breast. This test does not replace a clinical evaluation and does not provide a complete picture of your health on its own.
3. How does this test differ from other cancer-related tests?
This test specifically measures CA 15-3, distinguishing it from other cancer-related laboratory tests that may measure different biomarkers or support different clinical purposes. Its supported role is limited to monitoring treatment response and recurrence, not screening or diagnosis, so it reflects only what CA 15-3 levels can show about those specific aspects of care.
4. Do I need to fast before this test?
No fasting is required for this test. You should stop biotin consumption at least 72 hours prior to your blood collection.
5. How quickly will I get results?
Results are generally available in 4-6 days. Turnaround may take longer based on weather, holidays, or other lab delays.
6. How do I interpret the results?
Interpreting your CA 15-3 results depends on your specific result, your medical history, your treatment status, and other clinical findings. An elevated CA 15-3 level does not automatically mean cancer is present or has returned, since conditions such as liver disease or benign breast conditions can also raise levels. A normal result does not automatically rule out cancer. Your provider may also compare your results over time, since a rising level may suggest the disease is progressing or has returned, while a falling level may suggest improvement, though these results should be reviewed alongside other clinical information.
Disclaimer: Reference ranges may vary by laboratory. Listed ranges are general guidelines and may differ from those used by the performing lab. Always consult your healthcare provider for interpretation.
7. What should I do if my results are abnormal?
Review abnormal results with a qualified healthcare provider, who may consider additional evaluation based on your full clinical picture, your treatment history, and your overall health.
8. How often should I get tested?
How often you should be tested depends on your individual treatment and monitoring plan. Your healthcare provider can help determine an appropriate testing schedule based on your breast cancer treatment status and monitoring needs.
Pre-test preparation
No fasting is required. Stop biotin consumption at least 72 hours prior to your blood collection.
