Test Code CA 125 Cancer Antigen 125 (CA 125), Serum
Reporting Name
Cancer Ag 125 (CA 125), SClinical System Name: Carbohydrate antigen 125, serum (MEIA)
Useful For
Evaluating individuals' response to ovarian cancer therapy
Predicting recurrent ovarian cancer
This test is not useful for cancer detection screening in the normal population.
Specimen Required
Patient Preparation: For 12 hours before specimen collection do not take multivitamins or dietary supplements containing biotin (vitamin B7), which is commonly found in hair, skin, and nail supplements and multivitamins.
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 1 mL
Collection Instructions: Centrifuge and aliquot serum into plastic vial.
Collect 2.0 mL whole blood in a Gold SST tube.
Specimen Type
SerumSpecimen Minimum Volume
0.75 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 5 days | |
Frozen | 168 days |
Day(s) Performed
Monday through Friday
TAT: 3 - 5 days
Performing Laboratory
Mayo Clinic Laboratories in RochesterMethod Name
Electrochemiluminescent Immunoassay (ECLIA)
Method Description
The Roche Elecsys CA 125 II (cancer antigen 125) assay is a sandwich electrochemiluminescence immunoassay that employs a biotinylated monoclonal CA 125-specific antibody and a monoclonal CA 125-specific antibody labeled with a ruthenium complex. CA 125 in the specimen reacts with both the biotinylated monoclonal CA 125-specific antibody (mouse) and the monoclonal CA 125-specific antibody (mouse) labeled with ruthenium, forming a sandwich complex. Streptavidin-coated microparticles are added and the mixture is aspirated into the measuring cell where the microparticles are magnetically captured onto the surface of the electrode. Unbound substances are then removed with ProCell. Application of voltage to the electrode induces the chemiluminescent emission, which is then measured against a calibration curve to determine the amount of CA 125 in the patient specimen.(Package insert: Elecsys CA 125 II. Roche Diagnostics; V1.0, 09/2020)
Reference Values
Males: Not applicable
Females: <46 U/mL
Test Classification
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.CPT Code Information
86304
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
CA25 | Cancer Ag 125 (CA 125), S | 83082-8 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
CA25 | Cancer Ag 125 (CA 125), S | 83082-8 |
Report Available
1 to 3 daysReject Due To
Gross hemolysis | OK |
Gross lipemia | OK |
Forms
If not ordering electronically, complete, print, and send an Oncology Test Request (T729) with the specimen.