Middle stage lung cancer usually cannot be cured because lung cancer is a malignant disease and active treatment can only delay the survival time of patients, but cannot achieve the purpose of cure. Under normal circumstances, if patients in early and middle stages of lung cancer are in good health and can undergo surgery in time, and if they can cooperate with chemotherapy after surgery and maintain a good state of mind, the treatment effect is usually better and the 5-year survival rate may reach about 70% or even higher. However, in the middle and late stages of lung cancer, the treatment effect is usually poorer and the 5-year survival rate can reach 30%-50%. Once patients are diagnosed with lung cancer, they should maintain a positive attitude and cooperate with doctors for treatment to improve survival time as well as quality of life.