The five-year survival rate of malignant tumor of the upper lobe of the left lung varies from 5% to 70% after treatment, which should be analyzed according to the condition. Malignant tumors of the upper lobe of the left lung, i.e. lung cancer, has an unknown etiology, and the risk factors are related to smoking, heredity, gene mutation, etc. After the disease, it can be treated by surgery, radiotherapy, chemotherapy, etc. The specific prognosis after treatment is related to the stage of the disease. After treatment, the specific prognosis is more related to the stage of the disease, i.e. the stage according to the primary tumor, the degree of lymph node metastasis and whether distant metastasis occurs. After active treatment, the five-year survival rate of Stage I is about 70%; Stage II is about 50%; Stage III is about 15%; and Stage IV can be only 5%. In addition, the prognosis of small cell lung cancer is relatively poor if it is of high malignancy.