Follicular variant of papillary carcinoma arising from lingual thyroid.

Malignant transformation of ectopic lingual thyroid tissue is an uncommon event; only 43 cases have been reported in the literature. Only 10 of these cases were papillary carcinomas, in contrast to normal thyroid gland neoplasms, of which papillary tumors form the predominant group. We present a case of a follicular variant of papillary carcinoma originating from the lingual thyroid, along with a review of the literature. Our patient was treated with surgical excision followed by (131)I therapy. To date, only 2 other cases of a follicular variant of lingual thyroid tumor have been reported.