1. Children's Cancer Research Institute, St Anna Children's Hospital, Vienna, Austria;
2. Pediatric Hematology/Oncology, University of Palermo, Palermo, Italy;
3. Hospital Nacional de Pediatria J. Garrahan, Buenos Aires, Argentina;
4. Addenbrookes Hospital, Cambridge, United Kingdom;
5. Assistance-Publique Hôpitaux de Paris, Hopital Trousseau, Paris, France;
6. Childhood Cancer Research Unit, Department of Women and Child, Karolinska University Hospital, Stockholm, Sweden; and
7. Children's Research Institute, Children's National Medical Center, Washington, DC