Role for cytotoxic chemotherapy in patients with recurrent glioblastoma progressing on bevacizumab: a retrospective case series.

One hundred patients, aged 36-84 years (median 62 years) with recurrent glioblastoma (GBM), were treated previously with surgery, concurrent radiotherapy and temozolomide and postradiotherapy temozolomide followed by single-agent bevacizumab (BEV) at either first (60 patients) or second recurrence (40 patients). Patients were then treated following progression on BEV only with BEV and carboplatin (75 patients), cyclophosphamide (15 patients) or BCNU (ten patients; BEV+). Three hundred and sixteen treatment cycles (median: 2; range: 1-9) were administered of BEV+. There were 74 grade 3 adverse events in 29 patients (29%) and 20 grade 4 adverse events in ten patients (10%). Following 2 months of BEV+, 60 patients (60%) demonstrated progressive disease and discontinued therapy. Forty patients (40%) had neuroradiographic stable disease. Survival ranged from 1 to 12 months (median: 4 months). Median and 6-month progression free survival was 2.5 months and 5%, respectively. BEV plus a cytotoxic chemotherapy demonstrated limited efficacy in BEV-refractory GBM and emphasizes an unmet need in neuro-oncology in adults with BEV-refractory GBM.