Malignant giant cell tumor of the sphenoid

Malignant giant cell tumors (MGCTs) of the sphenoid sinus are extremely rare neoplasms. They are challenging to diagnose and difficult to treat because of their skull base location. To the best of our knowledge, we report the first case of a primary MGCT of the sphenoid arising in a patient with Paget's disease. A 77-year-old man presented with epistaxis and a history of Paget's disease. There was normal cranial nerve function although radiographic images disclosed a large mass centered in the sphenoid sinus and extending into the ethmoid and maxillary sinuses. Excisional biopsy revealed a MGCT composed of a cellular stroma with increased mitotic activity and necrosis with giant cells present throughout. Additional therapy was declined and the patient died with disease 7 months later. Because of their rarity, no treatment guidelines exist for the management of MGCTs of the sphenoid. We discuss both the diagnostic and therapeutic considerations based on a review of the pertinent literature.