1. Division of Pediatric Hematology and Oncology, Department of Pediatrics and Adolescent Medicine, and
2. Department of Oncology, University Children's Hospital, Zurich, Switzerland;
3. Department of Pediatrics,
4. Division of Pediatric Neurosurgery, Department of Neurosurgery, and
5. Department of Neuroradiology, University of Wuerzburg;
6. Department of Radiation Oncology, University of Leipzig;
7. Institute of Neuropathology, University of Bonn;
8. Department of Pediatric Oncology and Hematology, Charité-Universitätsmedizin Berlin; and
9. Institute for Medical Statistics, Medical University of Graz, Austria;
10. Department of Pediatric Hematology and Oncology, University Medical Center Hamburg-Eppendorf, Germany