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Catalog ID CA 15-3 CA 15-3

Important Note

Cancer antigen 15-3 (CA 15-3) is neither specific nor sensitive enough to be used as a cancer screen.

CPOE Test Name

CA 15-3, Serum

Synonyms

Cancer Antigen 15-3

Specimen Type

Serum

Specimen Requirements

5.0 mL Gold top SST tube; 2 mL blood

Causes for Rejection

Wrong container; insufficient quantity; improper labeling

Clinical Information

Carcinoma of the breast is the most prevalent form of cancer in women. These tumors often produce mucinous antigens that are large molecular weight glycoproteins with O-linked oligosaccharide chains. Tumor-associated antigens encoded by the human MUC-1 gene are known by several names, including MAM6, milk mucin antigen, cancer antigen (CA) 27.29, and CA 15-3.

CA 15-3 assay values are not elevated in most normal individuals and are frequently elevated in sera from breast cancer patients.

Reference Values

0.00 – 31.30 U/mL

Interpretation

Increasing and decreasing values show correlation with disease progression and regression, respectively. Increasing cancer antigen 15-3 (CA 15-3) assay values in patients at risk for breast cancer recurrence after primary therapy may be indicative of recurrent disease before it can be detected clinically and may be used as an indication that additional tests or procedures should be performed.

Some patients, who have been exposed to mouse antigens, whether in the environment or as part of treatment or imaging procedures, may have circulating antimouse antibodies. These antibodies may interfere with the assay reagents to produce unreliable CA 15-3 assay results. In rare cases, interference due to extremely high titers of antibodies to ruthenium or streptavidin can occur.

Turn Around Time

Routine: 2 – 4 hrs. Urgent/Emergent: 1 hr.

Performing Lab

Core Laboratory, AD 3301 706-721-2120

CPT / HCPCS Code

86300