Sign in →

Test Code CAG125 or LAB155 Cancer Antigen 125 (CA 125), Serum or Plasma

Important Note

Patient Preparation: For 12 hours before this test do not take multivitamins or dietary supplements containing biotin (vitamin B7), which is commonly found in hair, skin, and nail supplements and multivitamins.   Biotin can interfere with many immunoassay tests.

Specimen Requirements

Container Type:

Optimal: Gold or Mint*

*For STAT requests

Acceptable: Red or Green
Optimal Collection Volume: 

4.5mL; full tube
Minimum Volume:

1 mL whole blood
Collection Instructions:

Gently invert the sample 5-6 times after collection.
Specimen Transport:

Refrigerate
Processing Instructions: 

1. If serum, allow the specimen to clot for 30 minutes.

2. Centrifuge specimen within 2 hours of collection.

3. After centrifugation, specimen tubes without a gel barrier should have the serum or plasma aliquoted to a false bottom container.

4. Keep serum or plasma refrigerated until testing can be performed.

Specimen Stability

Specimen Type Temperature Time
Serum* Refrigerated 5 days
Room Temperature 8 hours
Frozen 6 months

*Note: Heparinized plasma in gel separator tubes is less stable than serum and is only suitable for add-on testing up to 2 days following sample collection.

Specimen Rejection Criteria

Hemolysis Mild OK; Moderate OK; Gross Reject
Lipemia Mild OK; Moderate OK; Gross Reject
Icterus Mild OK; Moderate OK; Gross Reject
Other Quantity not sufficient

Useful For

Evaluating a patient's response to ovarian cancer therapy

 

Predicting recurrent ovarian cancer

 

This test is not useful for cancer detection screening in the normal population.

 

Source: Mayo Medical Labs

Methodology

Roche Cobas - Electrochemiluminescence assay

 

Note: Values from different methods may give different results and cannot be used interchangeably.

Reference Ranges

< 35 U/mL

Interpretive

CA25 - Clinical & Interpretive: Cancer Antigen 125 (CA 125), Serum (mayocliniclabs.com)

Day(s) Performed

24/7

Expected TAT

Same day

Performing Laboratory

Bronson Laboratory, Chemistry - Kalamazoo

Sample Retention Time

7 days

CPT Code

86304

LOINC Code

10334-1