On the Horizon for High-Grade Gliomas in Children

Biologic Therapies

The Children’s Oncology Group recently opened a study evaluating a series of agents, heavily weighted toward biologic agents given during and after radiation therapy. Many of these agents have radiosensitization properties.

• Bevacizumab: One such agent is bevacizumab, a monoclonal antibody which is a vascular endothelial growth factor inhibitor. Although bevacizumab was shown to have a high response rate in adults with malignant gliomas, in the one large-scale pediatric study bevacizumab had minimal efficacy (31). 
• Others: Other biologic agents, including epidermal growth factor receptor antagonists, have yet to show a clear benefit but are being tested.

Surgery

Although surgical innovation and techniques, such as preoperative functional and intraoperative imaging, may contribute to decreasing morbidity from aggressive surgical resection of HGGs, they are unlikely to affect survival.

• Convection-enhanced delivery of therapeutic agents: One surgical nuance, however, that may be helpful, is the use of convection-enhanced delivery of agents directly into brain tumors and their surrounding environment (32). The surgeon can place this infusion system at the time of resection or re-resection, and high concentrations of agents can be delivered directly to the tumor, bypassing the blood-brain barrier.

Current Clinical Trials

The National Institutes of Health presently offer over 25 clinical trials involving the treatment high-grade gliomas in children (http://www.cancer.gov)