1. Department of Pediatrics, University Medical Center Schleswig-Holstein, Campus Kiel, Kiel, Germany;
2. Medical Statistics Unit, Department of Clinical Medicine and Prevention, University of Milano-Bicocca, Monza, Italy;
3. Institute of Human Genetics, Ruprecht-Karls University, Heidelberg, Germany;
4. Children's Cancer Research Institute and St Anna Kinderspital, Wien, Austria;
5. Department of Pediatrics Hemato-Oncology, Ospedale Pausillipon, Napoli, Italy;
6. Department of Pediatric Hematology and Oncology, Medical School Hannover, Hannover, Germany;
7. Pediatric Hemato-Oncology, Department of Pediatrics “Salus Pueri,” University of Padova, Padova, Italy;
8. Pediatric Hematology and Oncology, University Hospital Giessen, Giessen, Germany;
9. Pediatric Hematology and Oncology, University Hospital, Frankfurt, Germany;
10. Hematology/Oncology, Robert-Rössle-Klinik at the HELIOS Klinikum, Charité, Berlin, Germany;
11. Centro M. Tettamanti, Clinica Pediatrica Università Milano-Bicocca, Monza, Italy;
12. Department of Pediatric Hemato-Oncology, Ospedale Bambin Gesù, Rome, University of Pavia, Pavia, Italy;
13. Pediatric Oncology, University Children's Hospital Zürich, Zürich, Switzerland;
14. Department of Pediatric Hematology Oncology, Azienda Ospedaliero-Universitaria Meyer, Firenze, Italy;
15. Department.of Immunology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands;
16. Department of Pediatrics, University of Milano-Bicocca, Ospedale S. Gerardo, Monza, Italy; and
17. Department of Pediatrics, Ospedali Riuniti, Bergamo, Italy