OLIG2 and oligodendroglioma: We describe a male in his forties who presented with recurrent seizures and was found to have a heavily calcified lesion in the left temporal lobe and an additional lesion in the sacral region of the thecal sac; tissue biopsy of the sacral lesion demonstrated an oligodendroglioma-like morphology, strong synaptophysin and OLIG2 expression, and absent widespread GFAP staining, consistent with DGONC.