[1] Carl von Ossietzky Univ Oldenburg, Univ Childrens Hosp, Dept Pediat & Pediat Hematol Oncol, Klinikum Oldenburg AoR, Oldenburg, Germany
[2] Carl von Ossietzky Univ Oldenburg, Div Epidemiol & Biometry, Oldenburg, Germany
[3] Childrens Hosp Eastern Switzerland, Pediat Hematol Oncol Ctr, St Gallen, Switzerland
[4] Univ Lucerne, Fac Hlth Sci & Med, Luzern, Switzerland
[5] McMaster Childrens Hosp, Dept Pediat, Hamilton, ON, Canada
[6] McMaster Univ, Hamilton, ON, Canada
[7] Childrens Hosp Lucerne, Dept Pediat, Div Pediat Hematol & Oncol, Luzern, Switzerland
[8] Univ Hosp Essen, Pediat 3, Essen, Germany
[9] Univ Tubingen, Univ Childrens Hosp, Pediat Endocrinol, Tubingen, Germany
[10] Univ Augsburg, Fac Med, Diagnost & Intervent Neuroradiol, Augsburg, Germany
[11] Univ Bonn, Med Ctr, Inst Neuropathol, DGNN Brain Tumor Reference Ctr, Bonn, Germany