Patients will receive AZD4547 at a dose of 80mg bd on a continuous schedule, until disease progression. With the following hypothesis: P0: PFS6=15%, P1: PFS6=35%, with alpha=5% and power=80%, an initial cohort of 12 patients will be treated. If objective anti-tumor effects are observed, the cohort will be expanded to include a total number of 38 subjects. Grade II gliomas are also eligible but they will constitute an extra small cohort.