Introduction: The optimal duration of post-radiation temozolomide in newly diagnosed glioblastoma remains unclear. A combined analysis of 2 randomised trials, GEINO14-01 (Spain) and EX-TEM (Australia) studies, recently demonstrated no benefit from extending post-radiation temozolomide.
Objective: Here we report a sub-group analysis of elderly patients (EP).
Methods: EP (aged 65 years and over) were identified in the combined dataset. Relevant intergroup statistics were used to identify differences in tumour, treatment and outcome characteristics based on age. Survival was estimated using the Kaplan Meier method.
Results: Of the combined 205 patients, 57 (28%) were EP. 95% of EP were ECOG 0-1 and 65% underwent gross total resection compared with 97% and 61% of younger patients (YP) respectively. There were numerically less MGMT methylated (56% vs 63%, p=0.4) and IDH mutated (4% vs 13%, p=-.1) tumours in EP vs YP. At diagnosis, EP were more likely to receive short course radiotherapy (17.5% vs 6%, p=0.017), however per protocol completion was similar. At recurrence, there was a trend for EP to receive non-surgical options (96.2% vs 84.6%, p=0.06) or best supportive care (28.3% vs 15.4%, p=0.09). EP were less likely to receive bevacizumab at any time during treatment (23.1% vs 49.5%, p=0.0013). Median progression free survival was similar at 9.3months in EP and 8.5months in YP, with median overall survival being 20months for both.
Conclusion: EP in these trials had similar baseline characteristics but received less aggressive therapy at diagnosis and recurrence. Despite this, survival remains similar compared to YP. Further examination into assessment of fitness in EP and utility of salvage therapies is required.