Cancer Antigen 15-3

Cleveland Heartlab C, Test

Note: Cleveland HeartLab will begin transitioning CA 15-3 immunoassay testing to Quest Diagnostics, Chantilly VA, effective April 24, 2023. For patients who are currently being monitored by the Cleveland Clinic immunoassay, sample will be split and sent to both sites for testing. Results from both labs will be reported to aid in tumor marker re-baselining for a six-month period through October 27, 2023. Patients will only be billed for one CA 15-3 test.

CPT Code: 86300
Order Code: 5819
ABN Requirement:  No
Synonyms: CA 15-3; Breast Cancer Antibody
Specimen: Serum
Container: Gel-barrier tube (SST, Tiger Top)
Volume: 1.0 mL
-Note: 2.0 mL recommended for re-baselining
Minimum Volume: 0.5 mL
-Note: 1.0 mL recommended for re-baselining


  1. Collect and label sample according to standard protocols.
  2. Gently invert tube 10 times immediately after draw. Do not shake.
  3. Allow blood to clot 30 minutes.
  4. Centrifuge for 10 minutes.

Special Information: Results obtained with different methods or kits cannot be used interchangeably. Patients taking a biotin dose of up to 5 mg/day should refrain from taking biotin for 4 hours prior to sample collection. Patients taking a biotin dose of 5 to 10 mg/day should refrain from taking biotin for 8 hours prior to sample collection. Patients taking a biotin dose > 10 mg/day should consult with their physician or the laboratory prior to having a sample taken. Clinicians should consider biotin interference as a source of error, when clinically suspicious of the laboratory result.

Transport: Store serum at 2°C to 8°C after collection and ship the same day per packaging instructions included with the provided shipping box.


Ambient (15-25°C): 7 days
Refrigerated (2-8°C): 7 days
Frozen (-20°C): 28 days

Causes for rejection: Specimens other than serum; improper labeling; samples not stored properly; samples older than stability limits; gross hemolysis; gross lipemia

Methodology: Immunoassay (Siemens method: Quest Diagnostics, Roche method: Cleveland Clinic)

Turn Around Time: 2 to 3 days

Reference Range: See Laboratory Report

Clinical Significance: CA 15-3 may be useful for monitoring patients with metastatic breast cancer and certain ovarian cancers. The CA 15-3 values from sequential samples have a high correlation with the clinical course in most patients with metastatic breast cancer.

The CPT codes provided are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.