[1] Goethe Univ Frankfurt, Paediat Haematol & Oncol Childrens Hosp 3, D-60590 Frankfurt, Germany
[2] Childrens Hosp Philadelphia, Philadelphia, PA USA
[3] Childrens Hosp Gutierrez, Argentine Treatment Grp Acute Leukemias GATLA, Buenos Aires, DF, Argentina
[4] Hosp Nino Jesus, Madrid, Spain
[5] Univ Meyer, Azienda Osped, Florence, Italy
[6] Med Univ Lublin, Lublin, Poland
[7] Royal Marsden Hosp, Sutton, Surrey, England
[8] Hosp Sick Children, Toronto, ON M5G 1X8, Canada