Thyroid Cancer Monitoring
Definition / Purpose: 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.
Thyroglobulin Antibody≤1 IU/mL
Thyroglobulin, LC/MS/MS<0.4 ng/mL
When to order: Monitoring post thyroid cancer surgery
Pearl: If Thyroglobulin Antibody is negative, then Thyroglobulin is tested on the Beckman Coulter DxI. If Thyroglobulin Antibody is positive then, Thyroglobulin is tested by LC/MS/MS