Gliosarcoma with infratemporal fossa extension. Case report.

Gliosarcomas are bimorphic intraaxial tumors. Involvement of the skull base is highly unexpected. The authors present the case of a temporal lobe gliosarcoma with significant infratemporal fossa extension. This 55-year-old man presented with a 1-month history of severe progressive headache. Neurological examination was unremarkable except for bilateral papilledema. Magnetic resonance imaging revealed a 6-cm right temporal mass with extension into the infratemporal fossa. The patient underwent a right frontotemporal craniotomy together with drilling of the sphenoid ridge and middle fossa floor. The tumor consisted of intraaxial, intracranial as well as extradural, and extracranial components with extension to the posterolateral wall of the sphenoid sinus. It had a relatively well-circumscribed dissection plane. Gross-total resection was achieved, and the middle fossa floor was reconstructed using a rotated temporalis muscle flap. The postoperative course was uneventful except for hypesthesia in the distribution of the maxillary division of the right trigeminal nerve. The histopathological diagnosis was consistent with gliosarcoma. Radiotherapy and chemotherapy consisting of temozolomide were administered subsequently, and the patient was recurrence free 12 months after his initial diagnosis. In the presence of a mass lesion with both intraaxial and extracranial involvement, gliosarcoma should be considered among the differential diagnoses. Aggressive resection should be attempted, including the use of skull base surgical techniques to ensure an optimal outcome. The effect of skull base involvement to the overall treatment and outcome of patients with gliosarcomas would be difficult to determine given the rare occurrence of these lesions in such locations.