[1] Univ Med Ctr Hamburg Eppendorf, Inst Neuropathol, Hamburg, Germany
[2] Univ Med Ctr Hamburg Eppendorf, Dept Pediat Oncol, Hamburg, Germany
[3] Univ Childrens Hosp Wuerzburg, Dept Pediat Hematol & Oncol, Wurzburg, Germany
[4] Univ Hosp Geneva, Div Pediat Hematol & Oncol, Dept Pediat Obstet & Gynecol, Geneva, Switzerland
[5] Univ Childrens Hosp Rostock, Div Pediat Oncol & Hematol, Rostock, Germany
[6] Univ Childrens Hosp Zurich, Dept Oncol, Zurich, Switzerland
[7] Univ Klinikum Munster, Inst Biometrie & Klin Forsch, Munster, Germany
[8] Vivantes Klinikum, Kinder & Jugendmed, Berlin, Germany
[9] Univ Med Ctr Hamburg Eppendorf, Inst Med Biometry & Epidemiol, Hamburg, Germany
[10] Charite Univ Med Berlin, Dept Pediat Oncol Hematol, Berlin, Germany