Re-irradiation for recurrent glioblastoma multiforme.

As our understanding of normal brain tissue tolerance and radiation technology have improved, central nervous system (CNS) re-irradiation has garnered more attention; whereas, in the past there had been hesitancy due to late toxicity concerns, particularly radionecrosis (RN). There is minimal prospective data evaluating repeat radiation in recurrent gliomas. In this review, the rationale for and different approaches to re-irradiation will be discussed, and the biology and clinical impact of late CNS toxicity will be reviewed.