α-Subunit, Free (Endocrine Sciences)
Also known as: Pituitary Glycoproteins, Alpha Subunit
Use
Tumor marker
Special Instructions
The α-subunits of pituitary glycoprotein hormones TSH, FSH, LH, and hCG are immunologically indistinguishable, but with unique β-subunits that confer biological specificity. During pregnancy, levels of free α-subunit naturally increase. For optimal test processing and turnaround time, submit separate frozen specimens for each requested test when multiple tests are ordered.
Limitations
This assay may not differentiate between alpha subunits of different origin due to immunological similarities. Specificity may be compromised in the presence of relevant conditions such as pregnancy, leading to naturally elevated levels or in the presence of various tumors that elevate α-subunit levels. Caution is advised in interpretation, especially in pregnant patients or those with endocrine tumors.
Methodology
Immunoassay (ICMA)
Biomarkers
LOINC Codes
- 30316-4
- 30316-4
Result Turnaround Time
6-10 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.25 mL
Container
Serum from gel-barrier tube, serum from red-top tube, or serum from transfer tube
Collection Instructions
Transfer the serum into a Labcorp PP transpak frozen purple tube with screw cap (Labcorp No. 49482). Freeze immediately and maintain frozen until tested.
Storage Instructions
Freeze.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 1 day |
| Refrigerated | 1 day |
| Frozen | 200 days |