Overview of primary brain tumors: pathologic classification, epidemiology, molecular biology, and prognostic markers.

Contemporary neuropathology plays a key role in the multidisciplinary management of brain tumor patients, in part due to increased supplementation of histopathological assessments by molecular diagnostic tests involving brain tumor tissue. Several molecular tests have become routine for clinical practice, and not only contribute to a refinement of tumor classification, but also aid in improved prediction of prognosis and in development of a tailored approach to therapy. This review provides an overview of classification and grading of brain tumors, particularly neuroepithelial tumors, and describes genetic/epigenetic changes that have gained clinical significance for molecular diagnostic testing.