Radiation Oncology (London, England) | 2019
Survival benefits of hypofractionated radiotherapy combined with temozolomide or temozolomide plus bevacizumab in elderly patients with glioblastoma aged\u2009≥\u200975\u2009years
Abstract
Background and purposeThe purpose of this study was to evaluate the outcomes of elderly patients (aged ≥75\u2009years) with newly diagnosed glioblastoma (GBM), who were treated with hypofractionated radiotherapy comprising 45\u2009Gy in 15 fractions combined with temozolomide (TMZ) or TMZ and bevacizumab (TMZ/Bev).Materials and methodsBetween October 2007 and August 2018, 30 patients with GBM aged ≥75\u2009years were treated with hypofractionated radiotherapy consisting of 45\u2009Gy in 15 fractions. Twenty patients received TMZ and 10 received TMZ/Bev as upfront chemotherapy. O-6-methylguanine DNA methyltransferase (MGMT) promoter methylation status was analyzed by pyrosequencing. The cutoff value of the mean level of methylation at the 16 CpG sites was 16%.ResultsMedian overall survival (OS) and progression-free survival (PFS) were 12.9\u2009months and 9.9\u2009months, respectively. The 1-year OS and PFS rates were 64.7 and 34.7%, respectively. Median OS and PFS did not differ significantly between patients with MGMT promoter hypermethylation (N\u2009=\u200911) and those with hypomethylation (N\u2009=\u200916) (17.4 vs. 11.8\u2009months, p\u2009=\u20090.32; and 13.1 vs. 7.3\u2009months, p\u2009=\u20090.11, respectively). The median OS and PFS were not significantly different between TMZ (N\u2009=\u200920) and TMZ/Bev (N\u2009=\u200910) chemotherapy (median OS: TMZ 12.9\u2009months vs. TMZ/Bev 14.6\u2009months, p\u2009=\u20090.93, median PFS: TMZ 8.5\u2009months vs TMZ/Bev 10.0\u2009months, p\u2009=\u20090.64, respectively). The median time until Karnofsky performance status (KPS) score decreasing below 60 points was 7.9\u2009months. The best radiological responses included 11 patients with a partial response (36.7%). Grade 3/4 toxicities included leukopenia in 15 patients (50%), anorexia in 4 (13.3%), and hyponatremia during concomitant chemotherapy in 3 (10%).ConclusionOur hypofractionated radiotherapy regimen combined with TMZ or TMZ/Bev showed benefits in terms of OS, PFS, and KPS maintenance with acceptable toxicities in elderly patients with GBM aged ≥75\u2009years.