1. Department of Pediatric Hematology and Oncology Hospital Universitari Vall d´HebronVall d’Hebron Institut de Recerca (VHIR) Barcelona Spain
2. Department of Pediatric Hematology and Oncology Hospital General Universitario Gregorio Marañón Madrid Spain
3. Department of Pediatric Hematology and Oncology Hospital Infantil Universitario Niño Jesús Madrid Spain
4. Department of Pediatric Hematology and Oncology Hospital de la Santa Creu I Sant Pau Barcelona Spain
5. Department of Hematology Hospital Universitario Virgen del Rocío Sevilla Spain
6. Department of Pediatric Hematology and Oncology Hospital Clínico Universitario Virgen de la Arrixaca Murcia Spain