Histopathology and immunohistochemistry continue to be popular methods for predicting outcome in patients with malignant gliomas. This past year traditional histopathologic studies have stressed the importance of endothelial proliferation in the diagnosis of glioblastoma multiforme. Immunohistochemical proliferation markers, in particular MIB-1, may be useful in assessing oligodendroglioma behavior, whereas their role in malignant astrocytomas is less clear. Similarly, new studies on p53 and epidermal growth factor receptor immunohistochemistry in gliomas have demonstrated only limited predictive values.