Radiation Therapy for Glioblastoma

Fractionated radiation therapy improves overall survival compared with chemotherapy or best supportive care alone following biopsy or resection of newly diagnosed glioblastoma (HQE). Whether radiation therapy is indicated in a particular individual may depend on patient characteristics such as performance status (see 2.). (Strong)

Adding concurrent and adjuvant temozolomide to fractionated radiation therapy improves overall survival and progression free survival compared to fractionated radiation therapy alone, with a reasonably low incidence of early adverse events and without impairing quality of life (HQE). The guideline panel endorses fractionated radiation therapy with concurrent and adjuvant temozolomide as the standard of care following biopsy or resection of newly diagnosed glioblastoma in patients up to 70 years of age (see KQ2 for recommendations regarding patients older than 70). (Strong)

Adding bevacizumab to standard therapy for newly diagnosed glioblastoma (ie, fractionated radiation therapy with concomitant and adjuvant temozolomide) does not improve overall survival and is associated with a higher incidence of early adverse events (HQE). Bevacizumab may, however, prolong progression free survival (MQE). The panel does not recommend the routine addition of bevacizumab to standard therapy for newly diagnosed glioblastoma outside of a clinical trial. (Strong)

The addition of other systemic therapies to conventional radiation therapy with or without temozolomide remains investigational. (Strong)