Massive Skull Occult Metastasis of Follicular Carcinoma

Report of a Rare Case

Abstract

Follicular thyroid carcinoma accounts for 15% of thyroid cancer, which occurs more commonly in the elderly women. This type of thyroid cancer is usually characterized by a palpable nodule in thyroid gland, but occult metastasis of follicular thyroid carcinoma is rare and unusual. Herein, we report an 81-year-old woman with a history of palpable small mass at frontal bone with a progressive enlargement and an accelerated growth, with 1 in the last 12 months. At present, true size of tumor is 5.56×9.84 cm in frontal bone. Neuroimaging (computed tomography) of the skull bone demonstrated a lytic metastatic tumor. On the basis of histopathologic examination of the skull mass, diagnosis of metastatic follicular carcinoma was confirmed. Because of rare incidence of metastatic follicular thyroid carcinoma, this case is worth to be considered in detail.