Histopathological analysis of excised brain tumor tissue (H&E). A) Multiple zones of necrosis circumscribed by viable tissue (4 ×). B) Dense zone of small-cells with hyperchromatic nuclei and scant cytoplasm (10 ×). C) Zone of necrosis with dense pseudopalisades of small tumor cells at the periphery (20 ×). D) Tumor cell infiltration of the subpial zone of the cortex (20 ×).