[Interpretation of important issues of the secondary clinical practice guideline on management of primary malignant bone tumors by the Japanese Orthopaedic Association].

Primary malignant bone tumors are extremely rare. Osteosarcoma, chondrosarcoma, Ewing's sarcoma, and myeloma are the most common malignancy in bone. Osteosarcoma and Ewing's sarcoma are common in children and adolescents, and the tumors are high lethality due to the high rate of pulmonary metastasis. While chondrosarcoma, myeloma, and chordoma are more common in middle aged and elderly people. Japanese Orthopaedic Association (JOA) published the secondary clinical practice guideline on the management of primary malignant bone tumors. We put an emphasis on explanation some important issue of this guideline for help Chinese musculoskeletal tumor professionals in clinical practice.