[1] Univ klinikum Schleswig Holstein, Abt Endokrinol Diabetol & Stoffwechselmed, Med Klin 1, Campus Lubeck, Ratzeburger Allee 160, D-23538 Lubeck, Germany
[2] Charite Univ med Berlin, Dept Paediat Oncol & Haematol, Augustenburger Pl 1, Mittelallee 6A, D-13353 Berlin, Germany
[3] Free Univ Berlin, Augustenburger Pl 1, Mittelallee 6A, D-13353 Berlin, Germany
[4] Humboldt Univ, Berlin Inst Hlth, Campus Virchow Klinikum, Augustenburger Pl 1, Mittelallee 6A, D-13353 Berlin, Germany
[5] Univ klinikum Schleswig Holstein, Klin Kinder & Jugendmed Padiat Onkol & Hamatol, Campus Lubeck, Ratzeburger Allee 160, Haus A, D-23538 Lubeck, Germany
[6] Charite Univ med Berlin, Dept Haematol Oncol & Tumor Immunol, Augustenburger Pl 1, Mittelallee 11, D-13353 Berlin, Germany
[7] Free Univ Berlin, Augustenburger Pl 1, Mittelallee 11, D-13353 Berlin, Germany
[8] Humboldt Univ, Berlin Inst Hlth, Campus Virchow Klinikum, Augustenburger Pl 1, Mittelallee 11, D-13353 Berlin, Germany
[9] Univ Lubeck, Inst Med Biometrie & Stat IMBS, Univ klinikum Schleswig Holstein, Campus Lubeck, Ratzeburger Allee 160, V24, D-23562 Lubeck, Germany
[10] Univ klinikum Bonn, Zent Kinder & Jugendmed, Padiat Hamatol Onkol, Venusberg Campus 1, D-53127 Bonn, Germany
[11] Univ Lubeck, IT Ctr Clin Res, Haus 32, Ratzeburger Allee 160, D-23562 Lubeck, Germany
[12] Johannes Gutenberg Univ Mainz, Inst Med Biostat Epidemiol & Informat IMBEI, Div Childhood Canc Epidemiol, German Childhood Canc Registry,Univ Med Ctr, D-55101 Mainz, Germany