1. Department of Pediatric Oncology/Hematology, Erasmus University Medical Center-Sophia Children’s Hospital, Rotterdam, The Netherlands;
2. Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Lisboa, Portugal;
3. Cardiologia Pediatrica Medico Cirúrgica, Hospital Sta. Cruz, Lisboa, Portugal;
4. Centro Infantil Boldrini, Campinas, São Paulo, Brazil;
5. Dutch Childhood Oncology Group, The Hague, The Netherlands;
6. German Cooperative Study Group for Childhood Acute Lymphoblastic Leukemia, Hamburg, Germany;
7. Research Institute Children's Cancer Center Hamburg, Clinic of Pediatric Hematology and Oncology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; and
8. Princess Maxima Center for Pediatric Oncology, Utrecht, The Netherlands