Carbohydrate Antigen (CA) 19-9
Also known as: CA 19-9
Use
Monitor gastrointestinal, pancreatic, liver, and colorectal malignancies
Special Instructions
Values obtained with different assay methodologies should not be used interchangeably for serial testing. It is advised to use a consistent assay method for monitoring a patient's therapy course. This procedure is intended for one-time use only. Patients taking high-dose biotin supplements should stop biotin consumption at least 72 hours before the sample collection. Interference may occur due to biotin supplementation. For serial monitoring, order the test with the number 480053.
Limitations
CA 19-9 values can vary between testing procedures. Different CA 19-9 testing procedures are not directly comparable and could lead to erroneous interpretations. The test is not suitable for early detection of pancreatic carcinoma. It may produce elevated CA 19-9 levels in individuals with cholestasis due to liver excretion pathways. Patients with a Lewis a-negative/b-negative blood group cannot express the CA 19-9 antigen. Some patients may have varying CA 19-9 levels due to gene dosage effects. False findings can result from antibody interference, particularly in patients exposed to monoclonal mouse antibodies.
Methodology
Immunoassay (ECLIA)
Biomarkers
LOINC Codes
- 24108-3
- 24108-3
Result Turnaround Time
1 day
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.7 mL
Container
Gel-barrier tube (preferred) or red-top tube
Collection Instructions
If a red-top tube is used, transfer separated serum to a plastic transport tube.
Storage Instructions
Room temperature
Causes for Rejection
Citrate plasma specimen; improper labeling
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 14 days |
| Refrigerated | 14 days |
| Frozen | 14 days |