1. IRCCS Istituto Giannina Gaslini, Genova, Italy
2. Children's Cancer Research Institute, Vienna, Austria
3. Gustave Roussy, Villejuif, Paris, France
4. Fondazione IRCCS Istituto Nazionale dei Tumori, Milano, Italy
5. Pediatric Oncology Unit, Hospital Universitari I Politecnic La Fe, Valencia, Spain
6. Leeds Teaching Hospitals, NHS Trust, Leeds, United Kingdom
7. Ruth Rappaport Children's Hospital, Rambam Health Care Campus, Haifa, Israel
8. University of Hong Kong and Hong Kong Children's Hospital, Hong Kong SAR, China
9. University Hospital Ghent, Ghent, Belgium
10. University Hospital Lausanne, Switzerland
11. Children's Hospital, University of Helsinki, Helsinki, Finland
12. Jagiellonian University Medical College, Krakow, Poland
13. Department of Paediatrics, University Hospital of Aarhus, Denmark
14. University of Dublin, Ireland
15. Pediatric Clinic, Ljubljana, Slovenia
16. Agia Sofia Children's Hospital, Athens, Greece
17. Sydney Children's Hospital, Randwick, Australia
18. Institut Curie, Paris, France
19. Retired. Institute of Cancer Research and Royal Marsden Hospital, Sutton, United Kingdom
20. Department of Paediatrics, St Anna Children's Hospital and Children's Cancer Research Institute, Medical University, Vienna, Austria