Specimen Collection Manual and Test Catalog
THYROID CANCER (THYROGLOBULIN) MONITORING
Geisinger Epic Procedure Code: LAB1317 Geisinger Epic ID: 53193Serum
3 mL serum; minimum 1.5 mL.
Dietary supplements containing biotin may interfere in assays and may skew results to be either falsely high or falsely low. For patients receiving the recommended daily doses of biotin, draw samples at least 8 hours following the last biotin supplementation. For patients on mega-doses of biotin supplements, draw samples at least 72 hours following the last biotin supplementation.
Centrifuge and aliquot.
Refrigerated.
Room temperature: 6 days. Refrigerated: 7 days. Frozen: 28 days.
Hemolysis • Lipemia • Plasma • Icteric
The CPT codes provided by GML are based on AMA guidelines and are for informational purposes only.
If Thyroglobulin Antibody is negative, then Thyroglobulin is tested on the Beckman Coulter DxI (CPT code: 84432).
If Thyroglobulin Antibody is positive, then Thyroglobulin is tested by LC/MS/MS (CPT code: 84432).
Quest test code 90814, Thyroid Canc, Thyroglobulin Antibody,Thyroglobulin Tumor Markers,Thyroglobulin (Tg)
Thyroglobulin measurements are most useful in the postoperative monitoring of patients with papillary, follicular, and Hurthle cell carcinomas. However, approximately 20% of individuals develop autoantibodies to thyroglobulin. Since these antibodies interfere with immunoassay measurement of thyroglobulin, it is necessary to determine the presence or absence of antibodies before measuring thyroglobulin. This panel provides a sensitive method for determination of thyroglobulin autoantibodies, with subsequent measurement of thyroglobulin by either a sensitive immunoassay (Tg Ab negative samples) or LCMSMS (Tg Ab positive samples). The mass spectrometry assay has no interference from autoantibodies.