Abbreviations: DWI = diffusion-weighted imaging, FLAIR = fluid-attenuated inversion recovery, Gd-DTPA = Gd-diethylenetriamine penta-acetic acid, GFAP = glial fibrillary acidic protein, IDH1 = isocitrate dehydrogenase 1, Map2 = microtubule associated protein, MBP = myelin basic protein, MRI = magnetic resonance imaging, MRS = magnetic resonance spectrum.NeuN = neuronal nuclei, NF = neurofilament, Olig2 = oligodendrocyte transcription factor 2, PXA = pleomorphic xanthoastrocytoma, Syn = Vimentin, synapsin, WHO = World Health Organization. This evidence concerns the gene OLIG2 and pleomorphic xanthoastrocytoma.