1. Department of Pediatrics, Oncology and Haematology Medical University of Lodz Lodz Poland
2. Department of Hematology, Oncology, Hemostaseology and Stem Cell Transplantation RWTH Aachen University Aachen Germany
3. Center for Integrated Oncology Aachen Bonn Cologne Düsseldorf (CIO ABCD) Aachen Germany
4. Department of Paediatric Bone Marrow Transplantation, Oncology and Hematology Wroclaw Medical University Wrocław Poland
5. Division of Pediatric Hematology and Oncology, Medical Center, Faculty of Medicine Department of Pediatrics and Adolescent Medicine, University of Freiburg Freiburg Germany