1. The University of Tokyo , Department of Orthopedic Surgery, Tokyo , Japan
2. Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital Department of Musculoskeletal Oncology , Bunkyo-ku, Tokyo , Japan
3. Department of Musculoskeletal Oncology and Rehabilitation Medicine, National Cancer Center Hospital, Rare Cancer Center, National Cancer Center Hospital , Chuo-ku, Tokyo , Japan
4. The University of Tokyo, Department of Orthopedic Surgery , Tokyo , Japan