Molecularly targeted therapy for pediatric brain tumors.

Treatment of pediatric brain tumors remains a challenge because of the toxicity associated with conventional treatment and the relative resistance of tumors at the time of recurrence. The traditional approach of administering cytotoxic agents at the maximum tolerated dose is being supplanted by the development of molecularly targeted agents aimed at critical cellular changes that are responsible for the growth and spread of cancer cells. These agents theoretically should be more specific for tumor cells and less toxic to normal cells. While the idea of targeted therapy has generated much excitement in the oncology community, the degree of benefit to patients with central nervous system (CNS) tumors remains unclear. Numerous challenges remain in the development of these agents, including identification of meaningful targets, delivery of agents in sufficient quantity at the target site, and determination of any biologic response to these agents. This article discusses the rationale behind several of these agents and their use in pediatric patients with brain tumors.