1. Department of Pediatric Hematology-Oncology, Hospital Infantil Universitario Nino Jesus, Madrid, Spain
2. Hospital Clinico Universitario Virgen de la Arrixaca, El Palmar, Spain
3. Stem Cell Transplant Unit, Hospital Universitario Niño Jesus, Madrid, Spain
4. Department of Pediatric Cardiology, Hospital Infantil Universitario Nino Jesus, Madrid, Spain
5. Department of Radiology, Hospital Infantil Universitario Nino Jesus, Madrid, Spain