CA-15.3 is a blood test that measures the levels of a protein called cancer antigen 15-3 (CA 15-3) in the blood. This protein is produced by some types of breast cancer cells, and its levels can be used to monitor the progression of the disease or to determine the effectiveness of treatment.

Pre-test preparation for the CA-15.3 test typically involves fasting for 8-12 hours before the test is performed. The test is usually done in a lab or a doctor’s office, and it involves taking a sample of blood from a vein in the arm.

Common symptoms that may lead a healthcare provider to prescribe the CA-15.3 test include a lump or thickening in the breast, changes in the size or shape of the breast, or changes in the skin of the breast, such as redness or dimpling.

The CA-15.3 test is used to monitor the progression of breast cancer and to determine the effectiveness of treatment. Elevated levels of CA 15-3 in the blood can indicate that the cancer has spread or is growing, while lower levels can indicate that the cancer is responding to treatment. However, this test is not used as a diagnostic tool and should not be used alone to diagnose cancer.

Reference ranges and normal values for the CA-15.3 test vary depending on the lab that performs the test. Typically, levels of CA 15-3 in the blood are considered normal if they are less than 30 U/mL. However, it is important to note that a normal CA-15.3 test result does not necessarily mean that a person does not have cancer, as some people with breast cancer may have normal CA 15-3 levels.

Please note that this is general information and not a substitute for a professional medical advice, diagnosis, or treatment. It is important to consult with a qualified healthcare provider for proper diagnosis and treatment.