HG-79CASE OF AN UNUSUAL HIGH GRADE GLIOMA IN A 15 Y/O MALE WITH FEATURES OF EPITHELIOID GLIOBLASTOMA ARISING IN ASSOCIATION WITH PLEOMORPHIC XANTHOASTROCYTOMA (PXA)

Abstract

We present a case of a 15 y/o male who presented with symptoms of headache and left sided facial paresthesia who was found to have a right temporal mass on initial Magnetic Resonance Image of the Brain. He underwent an uneventful gross total resection of the mass and tumor sample was evaluated for diagnosis. His tumor exhibited an unusual morphology with a mixture of patterns that included components with features of PXA and epithelioid glioblastoma. Within the tumor, BRAF V600e mutation was detected. The tumor was IDH1 (R132H) negative and p53 positive. He had an MRI spine evaluation which was negative for disease and he was started on radiation along with temozolomide for treatment of his tumor. CLINICAL IMPORTANCE: The co-existence of PXA and overtly high grade epithelioid glioma is rare. The entities of epithelioid GBM and anaplastic epithelioid PXA, both frequently associated with BRAF mutation, are being defined and not well understood. This unique case may provide some insight into the relationship of PXA and epithelioid glioblastoma, a yet to be recognized entity in the World Health Association classification of tumors. We are following him closely for recurrence throughout his treatment course as the prognosis of this tumor based on available literature has yet to be defined. Additionally, the standard of care treatment for this unique tumor has yet to be established and it is unclear how effective BRAF inhibitors are in the treatment of this disease.