[1] Johannes Gutenberg Univ Mainz, German Childhood Canc Registry, IMBEI, Univ Med Ctr, D-55122 Mainz, Germany
[2] Univ Cologne, Dept Pediat Oncol & Hematol, Childrens Hosp, D-50931 Cologne, Germany
[3] Univ Cologne, CMMC, D-50931 Cologne, Germany
[4] Univ Saarland, Dept Pediat Hematol & Oncol, Homburg, Germany
[5] Univ Med Ctr Hamburg Eppendorf, Dept Pediat Hematol & Oncol, Hamburg, Germany
[6] Univ Munich, Dept Pediat Surg, Munich, Germany