Cancer Antigen-GI (CA 19-9)
Also known as: CA-GI
Use
The CA 19-9 test is crucial in monitoring various types of cancer including pancreatic, hepatobiliary, gastric, hepatocellular, and colorectal cancer. It utilizes the Roche CA 19-9 electrochemiluminescent immunoassay for quantitative analysis. This test should not be utilized as absolute proof of the presence or absence of malignant disease as values may vary with different testing methods or kits. Thus, it plays an important role in tracking cancer progression and treatment efficacy rather than initial diagnosis.
Special Instructions
Patient samples should be collected in a Serum Separator Tube (SST) or Plasma Separator Tube (PST), and other acceptable tubes include Green (lithium heparin), Lavender (K2EDTA or K3EDTA), or Pink (K2EDTA). It is essential that the specimen be allowed to clot completely at room temperature and separated from the cells as soon as possible or within 2 hours of collection.
Limitations
The CA 19-9 values cannot be used interchangeably across different test methods or kits. The test results are not definitive for diagnosing cancer but are used alongside other diagnostic methods to monitor disease progression or treatment responsiveness. It is important to note that not all cancer patients produce CA 19-9, and elevated levels may be due to non-malignant diseases.
FDA ApprovedNew York Approved
Methodology
Immunoassay (ECLIA)
Biomarkers
LOINC Codes
- 83084-4
Result Turnaround Time
0-1 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.5 mL
Container
ARUP Standard Transport Tube
Collection Instructions
Allow specimen to clot completely at room temperature. Separate from cells ASAP or within 2 hours of collection.
Storage Instructions
Refrigerated
Causes for Rejection
Specimens collected in sodium citrate or body fluid.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 5 days |
| Refrigerated | 2 weeks |
| Frozen | 3 months |