Historical contributions and future horizons of Japanese orthopaedic oncology: from surgical innovation to nationwide collaborations.

PURPOSE: Bone and soft tissue sarcomas are rare, heterogeneous malignancies presenting major diagnostic and therapeutic challenges. Over the past century, Japanese orthopaedic surgeons have occupied a unique position as both primary surgeons and comprehensive oncologists. On the occasion of the Centennial of the Japanese Orthopaedic Association (JOA), this review synthesizes the key historical milestones and future prospects of Japanese orthopaedic oncology. METHODS: A narrative synthesis was structured across five consolidated domains: (1) Surgical Innovation; (2) Advanced Basic Research and Novel Therapeutics; (3) The Japan Bone and Soft Tissue Tumor Registry (JBSTTR); (4) Nationwide Collaborative Research Groups and Multidisciplinary Platforms; and (5) Onco-Orthopaedics and Future Musculoskeletal Care. RESULTS: Japanese orthopaedic oncologists established quantitative surgical margin concepts, pioneered Total En Bloc Spondylectomy (TES) for spinal tumours, and developed recycled treated autografts (freezing, pasteurization, and irradiation). Translational research milestones encompass caffeine-potentiated chemotherapy, peptide-based immunotherapy, oncolytic viral therapies, Japan's first investigator-initiated clinical trial in oncology, and carbon-ion radiotherapy. Furthermore, a robust nationwide infrastructure has been forged through six decades of the JBSTTR alongside collaborative research engines-the Japanese Musculoskeletal Oncology Group (JMOG), the Japan Clinical Oncology Group Bone and Soft Tissue Tumor Study Group (JCOG-BSTTSG), and the Japan Ewing Sarcoma Study Group (JESS)-and the multidisciplinary platform Japanese Association of Sarcoma Treatment and Research (JSTAR). Expanding beyond primary sarcoma care, the conceptual framework of Onco-Orthopaedics has pioneered a holistic paradigm for managing locomotive syndrome in cancer patients "Cancer Locomo". CONCLUSION: The surgeon-led collaborative ecosystem in Japan bridges surgical precision, translational science, and nationwide multidisciplinary platforms, offering a sustainable model for advancing musculoskeletal oncology.