We also analysed the survival of patients after diagnosis for objective progressive disease. Patients which were treated for recurrent GBM, either by surgery, re-irradiation or chemotherapy, did have a longer survival compared to patients receiving best supportive care (BSC) in this situation. Prospective trials comparing BSC and re-irradiation or any other salvage-strategy in elderly patients are scarce; only one article analysed this topic and concluded, that salvage treatment for recurrent GBM could be beneficial . This comparison as well as our analysis are influenced by a selection bias, as patients with a better performance score are more likely to undergo a salvage treatment than patients with a poor OS. Concerning re-irradiation, an interval of less than 6 months between the first course of radiotherapy and progressive disease is usually believed as to short to undergo re-irradiation. As RChT can result in progression free survival of more than 6 months in elderly patients, especially when MGMT promotor hypermethylation is present , re-irradiation could become more frequent. Further studies, especially on the safety and efficacy of re-irradiation, are therefore highly recommended.