Prospective casecontrol study in glioma patients undergoing treatment with bevacizumab (Avastin). At present there are no data on the correlation between occurrence of arterial hypertension and clinical outcome in patients with glioma or anaplastic astrocytoma. We will investigate whether glioma patients developing hypertension under bevacizumab treatment have a better outcome in terms of progression free survival, response rate and overall survival than equally treated patients remaining normotensive. Moreover, we will describe the dynamics of change in blood pressure after administration of bevacizumab in those patients developing hypertension.