CA125 (Cancer Antigen 125); Cancer Antigen 125; Carbohydrate Antigen 125; OV Monitor; Ovarian Cancer-Related Antibodies; Cancer Ag 125 (CA 125), Serum; CA25
Test ID
CA25
General Information
Useful for:
Evaluating patients' response to ovarian cancer therapy
Predicting recurrent ovarian cancer
This test is not useful for cancer detection screening in the normal population.
Specimen Type
Serum
Specimen Requirements
Preferred: Serum Gel
Acceptable: Red Top
Minimum Sample Volume
0.75 mL
Stability
Refrigerated (preferred): 5 days
Frozen: 180 days
Limitations
Results cannot be interpreted as absolute evidence of the presence or absence of disease.
Serum markers are not specific for malignancy and values may vary by method. Values obtained with different assay methods cannot be used interchangeably.
Some individuals have antibodies to mouse protein (HAMA), which can cause interference in immunoassays that employ mouse antibodies. In particular, it has been reported that serum specimens from patients who have undergone therapeutic or diagnostic procedures that include infusion of mouse monoclonal antibodies may produce erroneous results in such assays. Rerunning the specimen in question after additional blocking treatment may resolve the issue.
No interference was observed from rheumatoid factors up to a concentration of 1200 IU/mL.
There is no high-dose hook effect at cancer antigen 125 (CA 125) concentrations of up to 50,000 U/mL.
