[1] Cambridge Univ Hosp NHS Trust, Dept Pediat Oncol, Cambridge CB2 0QQ, England
[2] Natl Ctr Child Hlth & Dev, Dept Paediat, Tokyo, Japan
[3] Univ Giessen, Nonhodgkin Lymphoma Berlin Frankfurt Muenster Stu, Dept Pediat Hematol & Oncol, D-35390 Giessen, Germany
[4] Univ Hosp, Dept Pediat, Padua, Italy
[5] Med Univ, Dept Bone Marrow Transplantat Children Oncol & He, Wroclaw, Poland
[6] Univ Amsterdam, Acad Med Ctr, Emma Kinderziekenhuis, Dept Paediat Oncol, NL-1105 AZ Amsterdam, Netherlands
[7] Univ Hosp, Dept Pediat Hematol Oncol, Louvain, Belgium
[8] Univ Gothenburg, Dept Pediat, Gothenburg, Sweden
[9] Inst Gustave Roussy, Biostat & Epidemiol Unit, Villejuif, France
[10] Univ Paris Sud, F-94275 Le Kremlin Bicetre, France
[11] Inst Gustave Roussy, Dept Pediat Oncol, Villejuif, France