Classification of gliomas

For almost a century, histopathological evaluation of gliomas has provided the gold standard for classification of these neoplasms. Indeed, the (neuro)pathologist is able to render an unequivocal diagnosis of glioma in most specimens and to indicate low- or high-grade malignant character of the lesion. It is increasingly clear, however, that the traditional histopathological diagnosis lacks the robustness and specificity that is needed for more tailored treatment of glioma patients. Even for the experienced neuropathologist, at least three factors may hamper reaching an unequivocal histopathological diagnosis on glioma tissue: (a) tissue quantity and quality, (b) lack of unequivocal histopathological criteria, and (c) incomplete representation of biology by morphology. Smart integration of information on the underlying molecular aberrations in the diagnosis of gliomas will undoubtedly result in a more sophisticated classification of these tumors. Modern neuropathology is thus rapidly moving toward a combined morphological and molecular approach, the challenge being to implement this approach in an affordable way that optimally serves the individual patients suffering from these neoplasms.