[1] UMC Utrecht, Radiat Oncol, Utrecht, Netherlands
[2] Inst Gustave Roussy, Radiotherapie, Villejuif, France
[3] Royal Marsden NHS Fdn Trust, Clin Oncol, Sutton Surrey, England
[4] Hosp Univ Vall dHebron, Oncol Radioterap, Barcelona, Spain
[5] UZ Leuven, Radiotherapie Oncol, Leuven, Belgium
[6] Univ Hosp Birmingham NHS Fdn Trust, Oncol, Birmingham, W Midlands, England
[7] Radboud Univ Nijmegen, Med Ctr, Radiat Oncol, Nijmegen, Netherlands
[8] St Joan Deu, Pediat Hematol & Oncol, Barcelona, Spain
[9] Utrecht Canc Ctr, Radiat Oncol, Utrecht, Netherlands
[10] Univ Klinikum Leipzig, Klin & Poliklin Strahlentherapie & Radioonkol, Leipzig, Germany
[11] Georg August Univ Gottingen, Pediat Hematol & Oncol, Gottingen, Germany
[12] Vrije Univ Amsterdam Med Ctr, Pediat, Amsterdam, Germany
[13] Georg August Univ, Pediat Hematol & Oncol, Gottingen, Germany