Reirradiation with concurrent bevacizumab for recurrent high-grade gliomas in adult patients

Purpose. - To analyse feasibility, prognostic factors and patterns of recurrence after concurrent reirradiation and bevacizumab for recurrent high-grade gliomas. Patients and methods. - Between 2009 and 2015, 35 patients (median 57-year-old; 21 men, 14 women) with WHO grade III (n=11)or grade IV (n = 24) gliomas were included in this retrospective and consecutive single-centre study. All patients received bevacizumab (median number of treatments: 12) concomitant with reirradiation (median dose: 45 Gy, median number of fractions: 18) for recurrence with median 22 months (range: 5.6-123.7 months) from first irradiation (median dose: 60 Gy). Results. - The median follow-up was 9.2 months from reirradiation. The median overall survival from reirradiation was 10.5 months (95% confidence interval [95% CI]: 4.9-16.1) and the progression-free survival from reirradiation was 6.7 months (95% CI: 2.9-10.5). The median overall survival from initial diagnosis was 44.6 months (95% CI: 32-57.1). No grade 3 toxicity or above was reported. Prognostic factors significantly correlated with better overall survival in univariate analysis were: age at least 55 (P=0.024), initial surgery (P=0.003), and 2 Gy equivalent dose (EQD2) at least 50 Gy at reirradiation (P=0.046). Twenty-two patients bevacizumab-naive at time of reirradiation had a significantly increased overall survival from reirradiation compared to patients treated with reirradiation after bevacizumab failure (17.7 vs. 5.4 months, P<0.001) as well as overall survival from initial diagnosis (58.9 vs. 33.5 months, P= 0.006). This outcome was similar in patients with initial glioblastomas (P= 0.018) or anaplastic gliomas (P= 0.021). There was no correlation between overall survival and gross tumour volume or planning target volume, frontal localization, or number of salvage therapies before reirradiation (P> 0.05). Conclusions. - Concomitant reirradiation with bevacizumab in high-grade recurrent gliomas shows encouraging results in terms of survival and toxicities. Our data suggest that reirradiation should be favoured at initiation of bevacizumab, with EQD2 at least 50 Gy. (C) 2017 Societe francaise de radiotherapie oncologique (SFRO). Published by Elsevier Masson SAS. All rights reserved.