1. Pediatric Oncology and Hematology Department, Hospital Sant Joan de Deu Barcelona Spain
2. Pediatric Hematology‐Oncology Department Hospital Universitario Niño Jesús Madrid Spain
3. Pediatric Hematology‐Oncology Department Hospital Materno‐Infantil Gregorio Marañón Madrid Spain
4. Pediatric Hemato‐Oncology Department Hospital Universitario La Paz Madrid Spain
5. Department of Pediatrics BioCruces Bizkaia Health Research Institute Hospital Universitario Cruces University of the Basque Country UPV/EHU Barakaldo Spain
6. Pediatric Oncology and Hematology Vall d'Hebron Barcelona Hospital Campus Barcelona Spain
7. Pediatric Hemato‐Oncology Department Hospital Universitario Miguel Servet Zaragoza Spain
8. Pediatric Hemato‐Oncology Department Hospital Clínico Universitario Salamanca Spain
9. Pediatric Hemato‐Oncology Department Hospital Universitario Son Espases Mallorca Spain
10. Pediatric Oncology and Hematology Department Hospital de la Santa Creu i Sant Pau Barcelona Spain
11. Pediatric Oncology and Hematology Department Hospital Clínico Universitario Virgen de la Arrixaca Instituto Murciano de Investigación Biosanitaria (IMIB) Murcia Spain
12. Pediatric Oncology and Hematology Department Hospital Virgen de la Salud Toledo Spain
13. Pediatric Oncology and Hematology Unit Hospital Universitario La Fe, La Valencia Valencia Spain
14. Pediatric Oncology and Hematology Department Hospital Universitario 12 de Octubre Madrid Spain
15. Pediatric Oncology and Hematology Department Hospital Clinico Universitario de Santiago de Compostela Santiago de Compostela Spain
16. Pediatric Oncology and Hematology Department Hospital Universitario Quiron Salud Madrid Spain
17. Pediatric Oncology Unit Hospitales Universitarios Virgen Macarena y Virgen del Rocio Sevilla Spain
18. Developmental Tumor Biology Laboratory Institut de Recerca Sant Joan de Déu Esplugues de Llobregat Barcelona Spain