The prognosis of lung cancer is closely related to the stage of the disease, type of pathology and physical condition of the patient. Early stage lung cancer has a 5-year survival rate of about 70% through surgical resection. If the disease develops further and liver metastasis, bone metastasis and brain metastasis appear, this stage is diagnosed as advanced lung cancer. The average survival period of patients is about 1-1.5 years. For patients with brain metastasis and bone metastasis of lung cancer, it is hard to determine exactly how long they can live. If the general condition of the patients is poor and they cannot tolerate radiotherapy and chemotherapy, the survival period will be significantly shortened, about 6 months. If the patient’s general condition is better, active radiotherapy and chemotherapy can be carried out, which can prolong the survival period of the patient, especially for patients with brain metastasis and bone metastasis, the condition can be well controlled by radiotherapy, and some patients can survive for more than 2-3 years.