1. University Bonn, Venusberg Campus 1, 53127 Bonn, Germany
2. Malformation Monitoring Centre Saxony-Anhalt, Medical Faculty, Otto-von-Guericke University, 39106 Magdeburg, Germany
3. Dr. von Haunersches Kinderspital, Department of Paediatric Surgery, University of Munich, 80539 Munich, Germany
4. Department of Pediatric and Adolescent Medicine, University Medical Center Augsburg, 86159 Augsburg, Germany
5. Centre for Childhood, Adolescents and Female Medicine, Paediatrics 5 (Oncology, Hämatology, Immunology), Olgahospital Klinikum Stuttgart, 70174 Stuttgart, Germany
6. Clinic for Childhood and Adolescent Medicine, Paediatric Oncology, University Hospital Leipzig (Universitätsklinikum Leipzig AöR), 04103 Leipzig, Germany
7. Clinic for Childhood and Adolescent Medicine, Paediatric Haematology and Oncology, University Hospital Dresden, 01307 Dresden, Germany
8. Clinic for Paediatric Hematology, Oncology and Immunology, University Childrens Hospital Düsseldorf, 40225 Düsseldorf, Germany
9. Clinic for Paediatric Hematology and Oncology, University of Münster, 48149 Münster, Germany
10. Department of Paediatric Haematology and Oncology, University Childrens Hospital Heidelberg, 69120 Heidelberg, Germany
11. Dr. von Haunersches Kinderspital, Department of Paediatric Haematology and Oncology, University of Munich, 80539 Munich, Germany
12. Department of Paediatric Haematology and Oncology, Asklepios Hospital Sankt Augustin, 53757 St. Augustin, Germany
13. Clinic for Childhood and Adolescent Medicine, Paediatric Haematology and Oncology, Medical Faculty Mannheim, University of Heidelberg, 69117 Heidelberg, Germany
14. Clinic for Childhood and Adolescent Medicine, Oncology Haematology, HELIOS Clinic Berlin-Buch, 13125 Berlin, Germany
15. Department of Pediatric Hematology and Oncology, University Hospital Bonn, 53127 Bonn, Germany
16. Department of Pathology, Section Paidopathology, University Hospital Bonn, 53127 Bonn, Germany
17. Department of Pediatric Hematology and Oncology, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany
18. Clinic of Paediatrics, Klinikum Dortmund, University Witten/Herdecke, 58448 Witten, Germany
19. Department of Pediatric Surgery and Urology, University Hospital Giessen-Marburg, Campus Marburg, 35037 Marburg, Germany
20. Department of Pediatric Surgery, University Hospital Giessen-Marburg, Campus Giessen, 35392 Giessen, Germany
21. Princess Máxima Center for Pediatric Oncology, 3584 Utrecht, The Netherlands
22. Division of Epidemiology, Institute of Social Pediatrics and Adolescent Medicine, LMU Munich, 80539 Munich, Germany
23. Department of Pediatrics and Adolescent Medicine, University Hospital Erlangen, 91054 Erlangen, Germany