1. Pediatric Hematology and Oncology; University of T; bingen; Tübingen Germany
2. Clinical Trials and Biostatistics Unit; IRCCS Istituto Oncologico Veneto; Padova Italy
3. Hematology-Oncology Division; Department of Women's and Children's Health; Padova University Hospital; Padova Italy
4. SIREDO Oncology Center (Care, Innovation and Research for Children, Adolescents and Young Adults with cancer); Institut Curie; Paris France
5. Clinic of Pediatrics; Dortmund Municipal Hospital; Dortmund Germany
6. Center for Dermato-Oncology; Department of Dermatology; Central Malignant Melanoma Registry of the German Dermatological Society; University Hospital Tübingen; Tübingen Germany
7. Pediatric Hematology and Oncology; University Children's Hospital Erlangen; Erlangen Germany
8. Pediatric Surgery, Department of Pediatrics, Padova University Hospital; Padova Italy
9. Department of Pediatric Surgery; Marciniak Hospital; Wroclaw Poland
10. Department of Pediatrics, Hematology and Oncology, Medical University; Gdansk Poland
11. Department of Pediatrics; Hadassah University Medical Center; Jerusalem Israel
12. Pediatric Oncology Unit; Fondazione IRCCS Istituto Nazionale dei Tumori; Milano Italy
13. Melanoma and Sarcoma Unit, Fondazione IRCCS Istituto Nazionale dei Tumori; Milano Italy
14. Pediatric Dermatology Department; Necker Hospital Assistance Publique; Paris France
15. Pediatric Hematology-Oncology Department; Centre Hospitalier Universitaire; Saint Denis de La Réunion France