Stereotactic radiosurgery and radiotherapy in the management of high-grade gliomas

Abstract

Despite intermittent waves of enthusiasm regarding varied treatment modalities, high-grade glioma (HGG) remains a highly lethal cancer for which the expected survival has only modestly improved over the past 50 years. Although infiltrative HGG does not present the most rational target for sharply defined single fraction radiosurgery (SRS), the local nature of the disease has encouraged clinicians and researchers to apply focused radiation as initial dose escalation or palliation of recurrences. This chapter documents the history of stereotactic radiation for HGG, selected published results, the technical application of focused radiation, and future directions in the field. The chapter concludes that the best current evidence does not support an improvement in outcome from the use of SRS for primary HGG, but that, for a very select group of patients with recurrent disease, SRS or fractionated stereotactic radiation may represent a safe, reasonable but palliative treatment. For recurrent HGG other treatment modalities have been tested in phase III trials and only such prospective investigation will define the exact role of stereotactic radiation in the salvage setting.