1. Clinic of Paediatric Oncology, Haematology and Clinical Immunology; Centre for Child and Adolescent Health; Medical Faculty; Heinrich-Heine-University Düsseldorf; Düsseldorf; Germany
2. Dr. von Haunersches Kinderspital; Ludwig-Maximilians-Universität; Munich; Germany
3. Medizinische Klinik und Poliklinik III; Klinikum Großhadern; Ludwig-Maximilians-Universität; Munich; Germany
4. Children's Hospital; University of Tübingen; Tübingen; Germany