[1] Univ Amsterdam, Emma Childrens Hosp, Dept Pediat Oncol, Amsterdam UMC, Amsterdam, Netherlands
[2] Princess Maxima Ctr Pediat Oncol, Heidelberglaan 25, Utrecht 3584 CS, Netherlands
[3] Univ Groningen, Univ Med Ctr Groningen, Beatrix Childrens Hosp, Dept Pediat Oncol Hematol, Groningen, Netherlands
[4] Dutch Childhood Oncol Grp, Utrecht, Netherlands
[5] Vrije Univ Amsterdam, Amsterdam UMC, Dept Pediat Oncol Hematol, Amsterdam, Netherlands
[6] Radboud Univ Nijmegen, Dept Hematol, Med Ctr, Nijmegen, Netherlands
[7] Univ Med Ctr, Wilhelmina Childrens Hosp, Dept Pediat Endocrinol, Utrecht, Netherlands
[8] Netherlands Inst Hlth Serv Res, Utrecht, Netherlands