Cancer Antigen 125
Ordering Recommendation

Evaluate and monitor ovarian cancer, usually epithelial subtype. Not recommended for monitoring breast cancer or germ tumors. Not a stand-alone test for ovarian cancer screening or diagnosis.

Quantitative Electrochemiluminescent Immunoassay
Within 24 hours
New York DOH Approval Status
This test is New York DOH approved.
Submit With Order
ARUP Consult®
Disease Topics
Specimen Required
Patient Preparation
Plasma separator tube or serum separator tube. Also acceptable: Green (sodium or lithium heparin), lavender (EDTA), or pink (K2EDTA). 
Specimen Preparation
Allow specimen to clot completely at room temperature. Separate serum or plasma from cells ASAP or within 2 hours of collection. Transfer 1 mL serum or plasma to an ARUP Standard Transport Tube. (Min: 0.5 mL) 
Storage/Transport Temperature
Unacceptable Conditions
Grossly hemolyzed specimens. 
After separation from cells: Ambient: 5 days; Refrigerated: 5 days; Frozen: 2 years 
Reference Interval
0-35 U/mL
Interpretive Data
The Roche CA 125 electrochemiluminescent immunoassay is used. Results obtained with different test methods or kits cannot be used interchangeably. The CA 125 test is used as an aid in monitoring response to therapy for patients with epithelial ovarian cancer. Serial testing for patient CA 125 values should be used in conjunction with other clinical methods for monitoring ovarian cancer. Patients with confirmed ovarian carcinoma may have pretreatment CA 125 values in the same range as healthy individuals. Elevations may be observed in patients with nonmalignant disease. Therefore, a CA 125 value, regardless of level, should not be interpreted as absolute evidence of the presence or absence of malignant disease.

Hotline History
Component Test Code*Component Chart NameLOINC
0080462Cancer Antigen 12510334-1
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
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