1. VU University Medical Center, Department of Pathology, Amsterdam, The Netherlands
2. VU University Medical Center, Department of Paediatrics, Division of Oncology/Haematology, Amsterdam, The Netherlands
3. Brain Tumor Center Amsterdam, Cancer Center Amsterdam, VU University Medical Center and Academic Medical Center, Amsterdam, The Netherlands
4. Stanford University School of Medicine, Department of Neurology, Neurosurgery and Pediatrics, Stanford, California, USA
5. Academic Medical Center, Department of Pathology, Amsterdam, The Netherlands
6. VU University Medical Center, Department of Neurosurgery, Amsterdam, The Netherlands
7. VU University Medical Center and Academic Medical Center, Neurosurgical Center Amsterdam, Amsterdam, The Netherlands
8. Prinses Máxima Center for Pediatric Oncology and University Medical Center Utrecht, Utrecht, The Netherlands