1. Cooperative Osteosarcoma Study Group, Paediatrics 5 (Oncology, Haematology, Immunology), Centre for Paediatric, Adolescent and Women’s Medicine, and Stuttgart Cancer Centre, Klinikum Stuttgart–Olgahospital, 70174 Stuttgart, Germany
2. Department of Thoracic Surgery, Faculty of Science, University of Tubingen, 72076 Tubingen, Germany
3. Heidelberg Ion Beam Therapy Centre (HIT), Department of Radiation Oncology, University Hospital Heidelberg, 69120 Heidelberg, Germany
4. Radiologic Institute, Centre for Paediatric, Adolescent and Women’s Medicine, Stuttgart Cancer Centre, Klinikum Stuttgart–Olgahospital, 70174 Stuttgart, Germany
5. St. Anna Children’s Hospital, University Hospital for Paediatric and Adolescent Medicine of the Medical University and St. Anna Children’s Cancer Research Institute (CCRI), 1090 Vienna, Austria
6. University Children’s Hospital Basel, 4031 Basel, Switzerland
7. Department of Paediatrics and Children’s Cancer Research Centre, Klinikum Rechts der Isar, School of Medicine, Technical University of Munich, 81675 Munich, Germany
8. Paediatric Haematology and Oncology, Klinikum Kassel, 34125 Kassel, Germany
9. Osteopathology Reference Centre, Institute of Pathology, Vivantes Klinikum im Friedrichshein, 10249 Berlin, Germany
10. Department for Paediatric Haematology and Oncology, University’s Children’s Hospital Muenster, 48149 Muenster, Germany