Thyroglobulin is a precursor to the thyroid hormones T4 and T3 and is present in the thyroid follicular cells. Nearly all thyroid follicular carcinomas stain for thyroglobulin and sometimes produce a focal staining pattern. Conversely, poorly differentiated carcinomas and non-thyroid adenocarcinomas do not stain for thyroglobulin. A panel of Anti-Thyroglobulin and Anti-Calcitonin is useful for identifying medullary thyroid carcinomas, whereas a panel of Anti-Thyroglobulin and Anti-TTF1 is useful for distinguishing between primary thyroid and lung neoplasms.
