1: HE, 40x: Sheets of neoplastic round to polygonal cells are interspersed with foci of hemorrhage (correlating to the gross image).
2: HE; 400x: Neoplastic cells vary in morphology with round, to polygonal, to elongate nuclei with finely stippled chromatin. The amount of cytoplasm varies, but for the most part is scant to mild. Atypia is abundant with karyomegaly and multinucleate neoplastic cells. Mitotic figures are common (arrow).
3: HE; 200x: Neoplastic cells spread along the glia limitans and the leptomeninges of the adjacent cortical tissue. This is a common feature of gliomas referred to as secondary structures.
NB: Immunohistochemistry for Olig2 confirmed the glial origin of the neoplastic cells; however, other IHC markers (GFAP, CNPase) failed to further define the lineage of the cells and therefore this was diagnosed as a poorly differentiated glioma.