A de novo gliosarcoma of the posterior fossa in a young patient with unique histological features: A rare case report

ABSTRACT

Gliosarcoma is characterized by a biphasic tissue pattern with alternating areas of glial and mesenchymal components, principally affecting adults, accounting for 2–8% of all glioblastomas, commonly located in the supratentorial fossa. Herein, we report a rare case of gliosarcoma with rhabdomyoblastic differentiation in a 36-year-old male who presented with headache, vomiting, and swaying while walking since one month with intact sensory and motor function. Computed tomography (CT) scan and magnetic resonance imaging (MRI) showed a right cerebellar mass with obstructing hydrocephalus. Surgical decompression and tumor resection were performed. Histological examination revealed a malignant glial component and a sarcomatous component along with rhabdoid cells. Immunohistochemistry showed cytoplasmic glial fibrillary acidic protein (GFAP) positivity and nuclear positivity of alpha mhalassemia/mental retardation syndrome X- linked (ATRX) in the glial component and desmin positivity in rhabdoid cells. The patient was given six cycles of temozolamide postoperatively and was uneventful. This report is the third gliosarcoma case, to my knowledge, with rhabdomyoblastic differentiation occurring de novo in the posterior fossa, which could explain the poor prognosis in these tumors. However, future studies are required to confirm this bad prognosis.