Carbohydrate Antigen 19-9 (CA 19-9), Serum
Use
Carbohydrate antigen 19-9 (CA 19-9) is used as an adjunct for the diagnosis and monitoring of pancreatic cancer. It can be potentially useful in differentiating patients with cholangiocarcinoma and primary sclerosing cholangitis (PSC) from those with PSC alone. CA 19-9 may be elevated in patients with gastrointestinal malignancies such as cholangiocarcinoma, pancreatic cancer, or colon cancer. Elevated serum CA 19-9 levels can also occur in benign conditions like cirrhosis, cholestasis, and pancreatitis.
Special Instructions
Patients should not take multivitamins or dietary supplements containing biotin (vitamin B7) for 12 hours before specimen collection. This may interfere with the accuracy and reliability of the test results.
Limitations
CA 19-9 is not specific or sensitive enough to be used as a cancer screening tool. Low values in individuals who do not express CA 19-9 are not informative for cancer recurrence. Serum CA 19-9 levels must be interpreted along with a clinical evaluation and other diagnostic procedures. Factors such as exposure to animal antigens and presence of anti-animal antibodies can interfere with assay reagents and produce unreliable results.
FDA ApprovedNew York Approved
Methodology
Immunoassay (Immunoenzymatic Assay)
Biomarkers
LOINC Codes
- 83084-4
- 83084-4
Result Turnaround Time
1-3 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
0.6 mL
Minimum Volume
0.5 mL
Container
Plastic vial
Collection Instructions
Within 2 hours of collection, serum gel tubes should be centrifuged. Red-top tubes should also be centrifuged, with serum aliquoted into a plastic vial.
Patient Preparation
Patient should not take multivitamins or dietary supplements containing biotin (vitamin B7) for 12 hours prior to specimen collection.
Causes for Rejection
Gross hemolysis will be rejected; gross lipemia and gross icterus are acceptable.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 8 hours |
| Refrigerated | 7 days |
| Frozen | 90 days |