Mucoepidermoid carcinoma post-radioactive iodine treatment of papillary thyroid carcinoma: unique presentation and putative etiologic association.

We report the development of mucoepidermoid carcinomas of the parotid gland in 2 adult patients after a relatively short duration of radioactive iodine (RAI) treatment of papillary thyroid carcinoma. Both instances, together with those previously reported, underscore the selective nature of the mucoepidermoid carcinoma phenotype development in patients with papillary thyroid carcinoma as a consequence of RAI treatment. Efforts to alleviate salivary pathophysiologic damage by RAI in these patients are warranted.