1. Department of Pathology Leiden University Medical Center Leiden The Netherlands
2. Leiden Center for Computational Oncology, LUMC Leiden The Netherlands
3. International Collaboration on Cancer Reporting Sydney NSW Australia
4. Department of Histopathology Royal National Orthopaedic Hospital Stanmore Greater London UK
5. Cancer Institute, University College London London UK
6. Bone Tumour Reference Centre Institute of Pathology, University Hospital Basel Basel Switzerland
7. Department of Radiology Leiden University Medical Center Leiden The Netherlands
8. Division of Molecular Pathology ProPath Dallas TX USA
9. Department of Pathology and Microbiology University of Nebraska Medical Center Omaha NE USA
10. Department of Pathology Vanderbilt University Medical Center Nashville TN USA
11. Institute of Biomedicine of Sevilla (IBiS), Virgen del Rocio University Hospital, CSIC, University of Seville Seville Spain
12. Department of Normal and Pathological Cytology and Histology School of Medicine, University of Seville Seville Spain
13. Department of Pathology Azienda Ospedaliera Universitaria di Padova Padova Italy
14. Department of Medicine University of Padua, School of Medicine Padua Italy
15. Department of Orthopaedics Huntsman Cancer Institute, University of Utah School of Medicine Salt Lake City UT USA
16. Department of Oncological Sciences Huntsman Cancer Institute, University of Utah School of Medicine Salt Lake City UT USA
17. Department of Tissue Pathology and Diagnostic Oncology Royal Prince Alfred Hospital Camperdown NSW Australia
18. Department of Pathology Massachusetts General Hospital Boston MA USA
19. Harvard Medical School Boston MA USA
20. Department of Pathology IRCCS Istituto Ortopedico Rizzoli Bologna Italy
21. Center for Sarcoma and Bone Oncology Dana‐Farber Cancer Institute Boston MA USA
22. Department of Diagnostic Pathology National Cancer Center Hospital Tokyo Japan
23. Rare Cancer Center National Cancer Center Hospital Tokyo Japan
24. Department of Pathology Brigham & Women's Hospital, Harvard Medical School Boston MA USA