Erosive bone destruction is defined as a malignant bone tumor with no definite boundary of destruction, no sclerotic ring envelope, and gradual migration between the tumor and normal bone. Erosive bone destruction is caused by malignant bone tumors and is also seen in bone infections. The following diseases are the causes of erosive bone destruction: 1. Bone tumors Bone tumors are tumors that occur in the bone or its appendages (blood vessels, nerves, bone marrow, etc.) and are common diseases. Like other tissues in the body, its exact cause is unknown; there are benign and malignant bone tumors, benign bone tumors are easily curable and have good prognosis, while malignant bone tumors develop rapidly, have poor prognosis and high mortality rate, and there is no satisfactory treatment method yet. Malignant bone tumors can be primary or secondary, which are metastasized from other tissues or organs in the body through blood circulation, lymphatic system to bones or directly invade bones. There is another category of lesions called tumor-like lesions. The tissues of tumor-like lesions do not have the characteristics of tumor cell morphology, but their ecology and behavior have the destructive nature of tumors, which are generally more limited and easily curable. Mesenchymal chondrosarcoma Mesenchymal chondrosarcoma is a rare malignant cartilaginous tumor, mostly occurring in young adults, Lichtenstein reported the first case in 1959, while Dowling reported the first case of mesenchymal chondrosarcoma originating from soft tissue in 1964. Until 1996, less than 200 cases were reported in foreign literature. 3. Central chondrosarcoma Central chondrosarcoma is a sarcoma whose cells tend to differentiate towards cartilage. It is divided into: central chondrosarcoma; peripheral chondrosarcoma; and periosteal chondrosarcoma. Treatment is surgical only, which has a fairly high cure rate, and radiotherapy and chemotherapy are ineffective for chondrosarcoma. Because of the slow growth of chondrosarcoma, local recurrence and metastasis can still occur more than 10 years after resection of the primary tumor.