Figure 2:

Histopathology of grade IV glioblastoma multiforme tumor. (a-c) Hematoxylin and eosin staining showing a poorly differentiated population of cells with multiforme cytologic features and some vaguely astrocytic features. There are abundant, often atypical mitotic figures, vascular proliferation, and necrosis. (d) Positive for GFAP immunoreactivity.