1. Department of Pediatric Hematology and Oncology, University Medicine Greifswald, 17475 Greifswald, Germany
2. Department of Paediatrics, St. Anna Children’s Hospital, Medical University of Vienna, 1090 Vienna, Austria
3. Department for Studies and Statistics and Integrated Research and Project, Children’s Cancer Research Institute (CCRI), St. Anna Kinderkrebsforschung GmbH, 1090 Vienna, Austria
4. Helios Klinikum Berlin Buch, 13125 Berlin, Germany
5. Clinic for Pediatric Hematology and Oncology, Charité University Medicine Berlin, 13353 Berlin, Germany
6. Department of Pediatric Oncology and Hematology, Jagiellonian University Medical College, 31-008 Krakow, Poland