When lung cancer reaches the middle and late stages, surgery may not be possible, but it can be combined with radiotherapy, chemotherapy and targeted drug therapy to control the development of the disease. Some lung cancers have brain metastases, which are stage IV distant metastases, but if they can be treated with targeted therapy, it can also prolong the survival period. Lung cancer is a very common malignant tumor of the respiratory system, which has no obvious symptoms in the early stage, and many of them show cough, coughing and blood in sputum similar to pneumonia, etc. Occupying lung lesions can be detected through CT examination. Once the occupying lung lesion is found, lung cancer may be considered, and pathological examination is needed, such as bronchoscopy and percutaneous lung aspiration biopsy for pathology. The diagnosis can be confirmed by pathological examination. If there is a chance of surgical treatment in the middle stage, you can consider surgery first; if there is no way to operate in the late stage, you can only consider other treatment methods.