Lung cancer is a kind of malignant tumor of respiratory system that is difficult to be cured, because it can easily metastasize and spread through blood and lymphatic channels. Once metastasis and proliferation of lung cancer have occurred, the clinical stage of lung cancer is advanced and the opportunity of radical surgery is lost. Although the treatments for advanced lung cancer include radiotherapy, chemotherapy, targeted therapy, immunotherapy, traditional Chinese medicine, etc., even with these treatments, the treatment of advanced lung cancer can only alleviate the symptoms, prolong the survival time of the patients and improve the quality of survival, but cannot achieve a clinical cure. However, even with these treatments, advanced treatment of lung cancer can only alleviate symptoms, prolong survival time and improve quality of life, but not achieve clinical cure, therefore, lung cancer is a relatively difficult malignant tumor to treat.