Cancer Antigen 15-3 (CA 15-3), Serum

Casandra

Casandra Test Code MC26878Version 1 (DRAFT)

Performing Lab

Lab Mayo Clinic LabLab Test ID CA153CPT Code 86300

Cancer Antigen 15-3 (CA 15-3), Serum

Clinical Use

Use

The Cancer Antigen 15-3 (CA 15-3) test is used for managing breast cancer patients in conjunction with clinical information and other diagnostic procedures. It assists in the early detection of disease recurrence in previously treated stage II and III breast cancer patients and helps monitor response to therapy in metastatic breast cancer patients. This test is not useful as a cancer screening test, as CA 15-3 assay values may not be elevated in normal individuals and are frequently elevated in sera from breast cancer patients. Nonmammary malignancies with reported elevated CA 15-3 values include lung, colon, pancreas, primary liver, ovary, cervix, and endometrium.

Special Instructions

For 12 hours before specimen collection, the patient should not take multivitamins or dietary supplements containing biotin (vitamin B7). If not ordering electronically, complete, print, and send an Oncology Test Request (T729) form with the specimen.

Limitations

Testing for cancer antigen 15-3 (CA 15-3) should be performed alongside other clinical methods for early detection of recurrence. Antibodies to mouse or other animal antibodies (HAMA) or heterophile antibodies may cause interference. The presence of antibodies to streptavidin or ruthenium can also interfere in this assay. Caution is advised in result interpretation, and laboratories should be alerted if results do not correlate with the clinical presentation.

Test Details

FDA Approved