Understanding the CA 15.3 Test
What It Is: The CA 15.3 test is a blood test primarily used as a tumor marker to monitor breast cancer progression or recurrence. It measures the levels of cancer antigen 15-3 (CA 15-3), a protein produced by breast cancer cells. While not specific for diagnosing breast cancer, this test provides valuable information for managing treatment and tracking disease status2.
Why It's Done:
Monitoring Breast Cancer:
The test helps evaluate the effectiveness of breast cancer treatments.
It assists in detecting cancer recurrence after treatment.
It tracks the progression of metastatic or advanced breast cancer2.
Understanding the Results:
Normal Levels:
Typically below 30 U/mL, suggesting no significant cancer activity3.
Slightly Elevated Levels:
May occur due to benign conditions like liver disease, ovarian cysts, or certain infections.
Significantly Elevated Levels:
Often associated with advanced or metastatic breast cancer, though other cancers can also cause high readings2.
Why Your Doctor Might Order This Test:
Symptoms of Breast Cancer:
If you have symptoms such as a lump in the breast, changes in breast shape, or unexplained weight loss, this test can help monitor the underlying cause.
Monitoring Treatment:
For patients undergoing treatment for breast cancer, this test helps monitor the effectiveness of the treatment2.
Symptoms That Might Prompt This Test:
Lump in the breast
Changes in breast shape or size
Unexplained weight loss
Fatigue
Lifestyle and Management:
Depending on your results, your healthcare provider might recommend further tests, treatments, or lifestyle changes to manage breast cancer effectively.
Regular monitoring and follow-up are essential for successful treatment