Skull metastasis from papillary thyroid carcinoma accompanied by neurofibromatosis type 1 and pheochromocytoma: report of a case.

We report here a 74-year-old woman with a skull metastasis from papillary thyroid carcinoma (PTC). In her medical history, she was diagnosed with neurofibromatosis type 1 (NF1) at age 28 years, and she underwent thyroidectomy for PTC at age 52 years and adrenectomy for pheochromocytoma (PC) at age 58 years. She was admitted to our hospital with an increased mass in the forehead. Head computed tomography (CT) showed an expansive, osteolytic, and solid tumor extending from the dura mater into the subcutis, destroying part of the frontal bone. Head magnetic resonance imaging (MRI) revealed that the tumor was chiefly extradural but partially invaded the dura mater. Cerebral angiography showed that the tumor was fed from a branch of the external carotid artery. She underwent surgery, and histological examination revealed that the skull tumor was a metastasis from PTC, indicating that skull metastasis occurred 23 years after curative surgery for PTC. The patient also underwent adjuvant radioiodine therapy. As little is known about skull metastases from PTC, we discuss its characteristics and the extremely rare combined occurrence of PC and PTC in an NF1 patient.