Generality
CA 15-3 (acronym for Cancer Antigen 15-3) is a protein, used as a tumor marker for breast cancer.
CA 15-3 is normally produced by breast cells; this protein, therefore, does NOT cause malignancy, but increases following its development.
What's this
Tumor Antigen 15-3 (CA 15-3) is a protein produced by breast cells.
In many of the people with malignant breast cancer, an increase in the production of CA 15-3 and the related tumor antigen 27.29 is observed (frequently, but not always).
This marker is especially useful for monitoring the course of the disease in an advanced stage and verifying the efficacy of the treatments undertaken. Furthermore, the detection of tumor antigen 15-3 over time keeps under control the possible resumption of the neoplastic process.
Because it is measured
Tumor antigen 15-3 belongs to the category of so-called tumor “markers”, ie those substances that can be found in increased quantities in the blood, urine or other body fluids in the presence of certain neoplasms.
In many cases, this marker is produced in excess by breast cancer cells and enters the bloodstream.
The 15-3 tumor antigen test may be requested as an aid in determining tumor characteristics and evaluating treatment options following the diagnosis of advanced breast cancer.
It should be noted that performing this test is not indicated in all situations, as CA 15-3 is not elevated in all women with breast cancer.
