[1] Charite Univ Med Berlin, Otto Heubner Ctr Paediat & Adolescent Med OHC, Dept Paediat Oncol Haematol, Berlin, Germany
[2] Free Univ Berlin, Berlin, Germany
[3] Humboldt Univ, Berlin, Germany
[4] Berlin Inst Hlth, Berlin, Germany
[5] Cambridge Prime Global Agcy, Knutsford, England
[6] Tech Univ Dresden, Univ Hosp Carl Gustav Carus Dresden, Dept Paediat Pneumol & Allergol, Dresden, Germany
[7] Charite Univ Med Berlin, Dept Pediat, Div Oncol & Hematol, Augustenburger Pl 1, D-13353 Berlin, Germany