Post-Treatment Gliosarcoma Extension into the Pterygomaxillary Fossa: Literature Review and Case Report.

Only four primary gliosarcoma case reports are described in the literature with transcranial (intradural to extradural) penetration into the region of the infratemporal fossa. This is the first report of a primary glioblastoma (GBM) that evolved into secondary or post-treatment gliosarcoma without evidence of a second tumor and with extension into the left pterygomaxillary fossa.