Sarcoma on the leg is mainly seen in two common clinical diseases, as follows: 1. It is mainly a common benign tumor on the body surface, such as sebaceous cyst or lipoma, whose clinical manifestations are clear borders, good mobility and soft texture of the mass, and usually requires further ultrasound examination for a clear diagnosis. After the diagnosis of benign tumors on the body surface such as sebaceous cysts or lipomas is clear, the masses are usually removed under local anesthesia to achieve the purpose of cure. 2. For synovial sarcoma, because it is a malignant tumor, radiotherapy or even chemotherapy is usually required after surgical removal.