Solitary primary intracranial extracerebral glioma. Case report.

A case is presented of a solitary primary extracerebral mixed glioma occurring in the right suprasellar and parasellar region of a 49-year-old woman who had bilateral temporal hemianopsia for 3 months. At craniotomy, the well demarcated outline and extracerebral location of the tumor suggested that it was a meningioma. However, its gliomatous nature was confirmed by identification of glial fibrillary acidic protein (GFAP) in the tumor cells. Review of nine reported solitary primary intracranial extracerebral gliomas, including the present case, revealed that they tended to occur in the third to fifth decades of life, in patients with an average age of 42 1/2 years, and without sexual predilection. All were supratentorial with a tendency to be situated in the vicinity of the Sylvian fissure. Only the glioma in the present case was at the cranial base. They were diagnosed as three astrocytomas, two glioblastomas, two oligodendrogliomas, one astroblastoma, and one mixed glioma. A suggestion is made that all these gliomas arose primarily from heterotopic neuroglia in the leptomeninges.