Medulloblastoma: toward biologically based management.

Medulloblastoma is the most common malignant brain tumor in children and, as such, has been the focus of tremendous efforts to genomically characterize it. What was once thought to be a single disease has been divided into multiple, molecularly unique subgroups through gene expression profiling. Each subgroup is not only unique in its origin and pathogenesis but also in the prognosis and potential therapeutic options. Targeted therapy of malignancies has long been the goal of clinical oncology. The progress made in the classification of medulloblastoma should be used as a model for future studies. With the evolution of epigenetic and genomic sequencing, especially when used in tandem with high-throughput pharmacologic screening protocols, the potential for subgroup-specific targeting is closer than ever. This review focuses on the development of the molecular classification system and its potential use in developing prognostic models as well as for the advancement of targeted therapeutic interventions.