pathology_of_human_tumor:the majority of the tumor present in the resected tissue appears only moderately cellular. the cells appear markedly atypical with large, hyperchromatic nuclei, numerous intranuclear cytoplasmic inclusions, and a few scattered atypical mitoses. these very abnormal appearing tumor cells are embedded within a fibrillary stroma. sprinkled throughout this stroma are smaller, round to spindled cells, which are often hyperchromatic with an occasional mitosis. in part b a small fragment of more normal appearing cerebral cortex contains a few infiltrating large pleomorphic tumor cells. part b also includes foci of more cellular tumor comprised of primitive appearing small round blue cells embedded within a somewhat granular appearing tumor matrix. mitotic features appear more abundant in these less well differentiated tumor foci.