Primary Osteogenic Sarcoma of the Skull

CASE DESCRIPTION A 21-year-old male was initially evaluated because of a large mass that had been growing for 7 months. The patient had been experiencing frequent headaches and tenderness at the site of the lump for about a month before being seen by the neurosurgeon. A computed tomography scan revealed a large mass, 12 cm 7 cm, involving the scalp extending from the right temporal region to the vertex. A magnetic resonance imaging (MRI) scan showed a large mass arising from the posterolateral aspect that was 90% extracranial and 10% intracranial on the right side of the skull. The MRI showed marked vascularity and neovascularity of the tumor. An angiogram was performed, which demonstrated that the mass was fed by the branches from the right external carotid artery. The patient subsequently underwent surgery for embolization of the right occipital and superficial temporal arteries and removal of the mass. Pathology evaluation of a specimen revealed a high-grade osteoblastic osteosarcoma.