Most mediastinal tumors need to be removed surgically. Even if they are benign, further development may cause perforation and the tumor may compress the surrounding organs. Therefore, surgical removal is preferable. Malignant mediastinal tumors require not only surgery, but also a combination of chemotherapy and radiation therapy and other treatments. In terms of prognosis, benign ones certainly have a good outcome, and even malignant thymomas have a better prognosis compared to cancers of other organs. The prognosis of malignant lymphomas and malignant germ cell tumors has improved due to advances in chemotherapy and radiotherapy. Due to the different types of mediastinal tumors, the attention in the convalescence varies. In benign tumors, if the tumor is removed, this will not leave any problems later. In malignant tumors, especially malignant lymphoma, malignant blastocytic tumors, thymic carcinoma, etc., longer adjuvant treatment (chemotherapy) is required. Thymoma can be combined with myasthenia gravis and lupus erythematosus, and it is necessary to continue further treatment after surgery. For myasthenia gravis, treatment with cholinesterase blocking drugs and steroids is available, with complete cure in about 40% and improvement in 50%. For lupus erythematosus, steroids are mainly used to treat the disease, and about half of the patients can get symptomatic relief. Excision of large tumors in the thorax.