Posterior fossa involvement in a recurrent gliosarcoma

Gliosarcoma (GSM) is a WHO grade 4 tumor and a variant of glioblastoma multiforme with predilection for the temporal lobe. We record, perhaps the first case in literature, of a temporal lobe GSM with recurrence involving the posterior fossa. A 50-year-old man presented to us with headache, vomiting, and lethargy of relatively recent onset. Magnetic resonance imaging revealed a well-circumscribed lesion in the left temporal lobe for which left temporal craniotomy with radical excision of the tumor was performed. Histopathology was suggestive of GSM. He presented to us within a month of the first surgery with a large recurrence involving the temporal lobe. He underwent a second surgery with radical excision of the tumor. Histopathology was confirmatory of GSM. He was administered concomitant chemotherapy and radiotherapy. Within a fortnight of starting adjuvant therapy, the bone flap started bulging and a repeat computed tomography scan revealed a large recurrence extending into the posterior fossa. The patient's relatives refused consent for third surgery and he finally succumbed on postoperative day 21. GSMs are aggressive tumors that have a temporal lobe predilection, but they may present anywhere in the brain. Detailed studies on larger cohort of cases are needed to understand the true nature of these biphasic tumors.