[1] Hannover Med Sch, Dept Pediat Hematol & Oncol, D-3000 Hannover, Germany
[2] Univ Hamburg, Dept Pediat Hematol & Oncol, Hamburg, Germany
[3] Goethe Univ Frankfurt, Frankfurt, Germany
[4] Univ Giessen, Dept Paediat Hematol Oncol, Oncogenet Lab, Giessen, Germany
[5] Charles Univ Prague, Univ Hosp Motol, Sch Med 2, Dept Pediat Hematol & Oncol, Prague, Czech Republic
[6] St Anna Childrens Hosp, Vienna, Austria
[7] Childrens Canc Res Inst, Vienna, Austria
[8] Univ Kindeklin, Munster, Germany