P13.20 * STEREOTACTIC RADIOTHERAPY FOR RECURRENT HIGH-GRADE GLIOMAS: A RETROSPECTIVE ANALYSIS

Abstract

PURPOSE: Numerous treatment options are available for recurrent high-grade gliomas (rHGG), including re-irradiation. Both fractionated stereotactic radiotherapy (FSRT) and radiosurgery (SRS) represent an optimal method to deliver high-dose radiotherapy to the small volume. Re-irradiation is often limited due to the dose-prescription and target volume. The primary end point of this retrospective study is to evaluate the efficacy of salvage SRS and FSRT in terms of overall survival; toxicity was analyzed as well. PATIENTS AND METHODS: Between 2004 and 2011, 128 patients (158 lesions) with recurrent high-grade gliomas (69% glioblastoma multiforme, WHO grade IV; 31% WHO grade III) were treated with CyberKnife stereotactic re-irradiation. FSRT was performed in 96 lesions with 3-5 fractions; SRS in 62 lesions. The median time from first irradiation and SRS re-irradiation was 12 months (range 6-171 months). RESULTS: A median survival time from the date of diagnosis was 32 months (95% CI, 25-43). Median survival time from the re-irradiation treatment was 11.5 months (95% CI, 10-12). Multivariate analysis confirmed that younger age and salvage surgery after SRS were associated with a significant improvement in survival. There have been 19 patients (15%) of G1-G2 acute toxicity (with headache, nausea, fatigue and alopecia) and 7 pts. (6%) of G3-G4 late toxicity (radiation-induced necrosis and neurological deterioration). CONCLUSIONS: Salvage re-irradiation with CyberKnife stereotactic radiotherapy for recurrent high-grade gliomas is safe and well tolerated. This strategy can be considered an effective treatment for recurrent HGG.