Thyroglobulin

Test Code

THY

Alias/See Also

TG
Quantitative Thyroglobulin without Thyroglobulin Antibodies

Quest Code
15561

CPT Codes
84432

Preferred Specimen

2 mL serum collected in a serum separator tube (SST)

Minimum Volume

1 mL

Other Acceptable Specimens

2 mL serum collected in a no additive (red-top) tube, transferred to a plastic screw-cap vial

Transport Temperature

Refrigerated

Specimen Stability

Room temperature: 7 days
Refrigerated: 7 days
Frozen: 28 days

Methodology
Immunoassay

Setup Schedule

Tuesday-Saturday a.m.

Report Available

Same day

Clinical Significance

Thyroglobulin (TG) is a secretory product only of the thyroid gland. The major clinical use of serum TG measurement is to monitor, but not to diagnose, patients with well-differentiated thyroid cancers. The measurement of thyroglobulin, after thyroidectomy and ablation of the thyroid gland, is useful to determine metastasis. Deficient TG synthesis is observed in infants with goitrous hypothyroidism. With immunometric assays (sandwich assays), TGAB interference typically produces inappropriately low TG results, most likely caused by endogenous TG immune complexes that block one or more of the reagent Ab from binding endogenous TG.

Performing Laboratory
Quest Diagnostics Nichols Institute
Chantilly, VA

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.