1. SIREDO Oncology Center (Care, Innovation and Research for Children, Adolescents and Young Adults with Cancer) Institut Curie, PSL University Paris France
2. Clinic of Pediatrics Dortmund Municipal Hospital Dortmund Germany
3. Pediatric Oncology Unit Fondazione IRCCS Istituto Nazionale dei Tumori Milan Italy
4. Department of Pediatrics, Hematology and Oncology, Medical University of Gdańsk Gdańsk Poland
5. Center for Pediatric Oncology and Hematology Vilnius University Hospital Vilnius Lithuania
6. Institute of Pathology Friedrich‐Alexander University Erlangen‐Nürnberg (FAU) Erlangen Germany
7. Department of Hematology and Oncology University Clinic for Children's Diseases, Medical Faculty, Ss. Cyril and Methodius University of Skopje Skopje North Macedonia
8. Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology Moscow Russian Federation
9. Department of Pediatrics Clinical Hospital Center Rijeka Croatia
10. Hematology‐Oncology Division, Department of Pediatrics Padova University Hospital Padua Italy
11. Pediatric Hematology and Oncology, Children's Hospital Eberhard‐Karls‐Universitaet Tuebingen Tübingen Germany
12. Department of Surgery, Division of Plastic Surgery University of California San Diego California USA
13. Radiation Oncology Department Baclesse Cancer Center Caen France
14. Head and Neck Surgery Department Gustave‐Roussy Cancer Campus Villejuif France