Thyroid Follicular Carcinoma Metastasized to the Lung, Skull, and Brain 12 Years After Initial Treatment for Thyroid Gland

A 65-year-old woman presented with multiple metastases from thyroid follicular carcinoma to the lung, skull, and brain. The skull and brain tumors had been successfully treated by surgery, thyroxine supplementation, and radiosurgery until she died of sudden intracerebral hemorrhage which had no connection with tumor treatment. The lung tumor was treated by conventional irradiation and radioactive ablation. Well-differentiated thyroid carcinoma is a slowly progressive tumor. Follicular carcinoma is thought to have the most optimistic prognosis even with metastases to the lymph nodes and lung. Radioactive ablation using iodine-131 is widely used to treat the primary and/or metastatic lesion. However, the prognosis for patients with brain metastases is poor. Intracranial metastasis of this tumor is rare, but has a mean posttreatment survival of around 12 months. Surgical excision of the metastatic intracranial lesion may be the only effective treatment.