Pathologic Effects of Radiation on the Thyroid Gland

The thyroid gland is virtually unique since it can be affected by both external radiation (and thus, it shares with other organs histopathologic changes due to irradiation effects) and by the so-called "internal" radiation, wherein administration of radioactive iodide preferentially affects the thyroid gland (almost to the exclusion of all other organs). This review will focus on both types of radiation and the changes that can be seen acutely and chronically in the thyroid after it has been subjected to irradiation. In addition, the neoplastic potential of radiation exposure on thyroid follicular epithelium will be presented and illustrated.

Keywords: Radiation, carcinoma, thyroid, thyroiditis.