Successful Treatment of Cavernous Sinus Metastasis from Follicular Thyroid Carcinoma with Lenvatinib

Radioiodine-refractory distant metastases in well-differentiated thyroid carcinomas are rare but pose a significant diagnostic and management challenge. Follicular thyroid carcinoma which is a type of well-differentiated carcinoma, is known for its hematogenous spread. Various sites of distant metastasis have been described. We report the first-ever case of radioiodine-refractory metastasis at the cavernous sinus, arising from follicular thyroid carcinoma. The atypical site of metastasis and management complexity of radioiodine-refractory disease is discussed in this article.