Osteosarcoma can be felt as a lump, and generally does not show symptoms in the early stages. Once symptoms appear and a mass is palpable, it is usually at the mid to late stage. The main manifestation is pain, with a local mass; the pain tends to be persistent and primarily occurs at night. Additionally, local veins may be distended, and the patient may exhibit cachexia phenomena, with gradual weight loss. Comprehensive body examinations can reveal early lung metastasis in the patient. If there is no metastasis, limb-sparing or amputation surgeries can usually be performed. The presence of distant metastases directly affects the patient's survival time. Early radiographic investigations show a Codman's triangle, and further pathology tests are needed for confirmation. After confirmation, early surgical treatment, combined with postoperative chemotherapy, can improve the patient's survival time, generally with a five-year survival rate of over 50%.