RESUMO
Gliofibroma is a rare astrocytic tumor, composed of a glial component ranging from benign to high grade of malignancy and a consistently benign mesenchymal component. Its exact biological behavior is not fully known. In addition, histogenesis and prognostic factors are also still debatable. We herein present a rare case of gliofibroma in a 25-yr-old male with seizure. A computed tomographic scan of the brain showed a 1.5 cm-sized, enhancing mass with calcification. Histologically, the tumor consisted of glial fibrillary acidic protein (GFAP)-positive glial cells admixed with a mesenchymal component and extensive collagen lay down. The glial cells displayed variable cellularity, but without mitosis or necrosis. Since the MIB-1 labeling index was up to 35.8% in the cellular areas of the glial component, it could be considered to be a predictor of worse prognosis.