1. SIREDO Oncology Center (Care, Innovation and Research for Children, Adolescents and Young Adults with Cancer) Institut Curie PSL University Paris France
2. Pediatric Oncology Unit Fondazione IRCCS Istituto Nazionale dei Tumori di Milano Milan Italy
3. Clinic of Pediatrics Dortmund Municipal Hospital Dortmund Germany
4. Pediatric Hematology‐Oncology Department Centre Hospitalier Universitaire Saint Denis Réunion Island France
5. Department of Pediatric Surgery Marciniak Hospital Wroclaw Poland
6. Department of Pediatrics, Hematology and Oncology Medical University Gdansk Poland
7. Pediatric Surgery, Department of Pediatrics Padova University Hospital Padua Italy
8. Cruces University Hospital Barakaldo‐Bizkaia Spain
9. Pediatric Oncology Unit Oncology Institute “Prof. Dr. Al. Trestioreanu” Bucharest Romania
10. Department of Hematology and Oncology University Children's Hospital University of Belgrade Belgrade Serbia
11. Pediatric Hematology Unit Kaplan Medical Center Rehovot Israel
12. Department of Pediatrics, Clinical Hospital Center Rijeka University of Rijeka Rijeka Croatia
13. Pediatric Hematology and Oncology, Children's Hospital Eberhard‐Karls‐Universitaet Tuebingen Tübingen Germany
14. Department for Studies and Statistics and Integrated Research, St. Anna Children's Hospital Children's Cancer Research Institute Vienna Austria
15. Hematology‐Oncology Division, Department of Women's and Children's Health Padova University Hospital Padua Italy