1. Department of Neurosurgery, VU University Medical Center, Amsterdam, The Netherlands
2. Department of Pediatric Oncology, VU University Medical Center, Amsterdam, The Netherlands
3. Neuro-oncology Research Group, Cancer Center Amsterdam, VU University Medical Center, Amsterdam, The Netherlands
4. Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
5. Department of Pathology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
6. Department of Pathology, PAMM, Eindhoven, The Netherlands
7. Department of Pathology, VU University Medical Center, Amsterdam, The Netherlands