Chromogranin A
Use
An aid in the detection and monitoring of neuroendocrine cancers including pheochromocytomas, medullary thyroid carcinomas, functioning and nonfunctioning islet cell and gastrointestinal amine precursor uptake and decarboxylation tumors, and pituitary adenomas. A possible adjunct in outcome prediction and follow-up in advanced prostate cancer.
Special Instructions
Values obtained with different assay methods should not be used interchangeably in serial testing. It is recommended that only one assay method be used consistently to monitor each patient's course of therapy. If serial monitoring is required, please use Chromogranin A (Serial Monitor) [480847] to order.
Limitations
Elevated CgA levels may occur in non-NEN malignancies like hepatocellular carcinoma and breast cancer. CgA levels are also elevated in various non-neoplastic conditions, such as gastrointestinal disorders, cardiovascular disorders, rheumatoid diseases, kidney and liver impairments, and chronic use of proton pump inhibitors. Poorly differentiated NETs have low sensitivity for CgA, and levels may be normal in patients with localized, non-functional NETs. Patients with multiple endocrine neoplasia type 1 (MEN) may show no increase in CgA. False positives can occur in patients with heterophile antibodies.
Methodology
Immunoassay (Immunofluorescent)
Biomarkers
LOINC Codes
- 9811-1
- 9811-1
Result Turnaround Time
3-5 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
0.5 mL
Minimum Volume
0.3 mL
Container
Gel-barrier tube
Collection Instructions
Transfer separated serum to a plastic transport tube.
Storage Instructions
Room temperature
Causes for Rejection
Gross icterus; gross hemolysis; gross lipemia
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 7 days |
| Refrigerated | 14 days |
| Frozen | 3 months |