1.Screening and early detection The 5-year survival rate of surgically resected stage IA lung cancer reaches 70%, but more than 75% of patients start with incurable locally advanced stage or have metastasis, and the 5-year survival rate of the latter is less than 5%. Therefore, early detection and diagnosis of lung cancer can significantly improve the survival rate of patients after treatment, and efforts to detect and diagnose lung cancer early by screening have been ongoing. The target population for screening is those at high risk of developing lung cancer: men, 45 years of age or older, with a smoking index >400 (number of cigarettes smoked/day x number of years of smoking) and a family history of tumors. In the 1960s, chest radiograph screening was introduced, and in the 1970s and 1980s, several randomized controlled trials of chest X-ray screening were published, including a large clinical trial sponsored by the National Cancer Institute and completed by several large hospitals. The results all showed that although more cases were feasible for early surgical resection in the screening group, the tumor-related mortality rate was similar to that in the clinical group, concluding that screening with chest radiographs did not reduce mortality from lung cancer. Later, sputum smear screening was used instead. By the end of the 1990s, low-dose chest CT was used in Europe, America and Japan to carry out lung cancer screening. The American Institute for Cancer Research launched the National (U.S.) Cancer Screening Trial in August 2002, enrolling 53,454 current and former heavy smokers over 20 months and randomly assigning them to receive low-dose spiral CT and standard chest X-rays. Results of the clinical trial were released on November 4, 2010, and showed 245.7 lung cancer deaths per 100,000 person-years in the CT group compared to 308.3 in the chest X-ray group, with 354 deaths in the CT screening group compared to 442 deaths in the chest X-ray screening group. Therefore, it was concluded that the lung cancer mortality rate was reduced by 20.3% and the study was recommended to be terminated. This is the first clear evidence of a significant reduction in lung cancer mortality provided by a randomized controlled screening trial. However, there is also an issue of economic-benefit ratio from an economic health perspective, i.e., high cost of payment and small benefit. As a developing country, it is premature to use low-dose chest CT for large-scale lung cancer screening in China. 2.Behavioral interventions Lung cancer is mainly a disease caused by environmental factors, among which smoking is an important carcinogenic factor, so discouraging smoking has positive significance for the prevention of lung cancer. 3.Smoking It is known that about 80% of lung cancer is caused by smoking. If smoking is controlled, the incidence of lung cancer can be greatly reduced and most of lung cancer can be prevented. For smokers, scientific and effective activities should be carried out to persuade them to quit smoking. The relative risk of lung cancer in smokers is 10-15 times higher than that in nonsmokers. After a smoker has quit smoking for 10 years, the risk of lung cancer will be 30% to 50% lower than that of a continuing smoker. There are already some countries and regions that have received significant results in controlling smoking. The anti-smoking campaign in the United States began in the 1960s, and after more than 30 years of effort, the incidence of lung cancer among men in the United States began to level off in the 1990s due to a decline in smoking rates, and has gradually declined since then, thus demonstrating the efficacy of the anti-smoking campaign. -On August 28, 2005, the Standing Committee of the National People’s Congress (NPC) ratified the WHO Framework Convention on Tobacco Control (FCTC), demonstrating China’s image and determination as a responsible power to work with all parties to curb the harm of tobacco and protect the public’s health rights. determination. In addition to not actively smoking, care should be taken to avoid passive smoking as much as possible, and you should try to avoid smokers in public places to avoid the hazards of secondhand smoke. 4.Occupational protection Epidemiological, pathological and experimental evidence of occupational carcinogenic factors include inorganic arsenic, asbestos, chromium, coal tar and other combustion products of coal. For mines where radioactive ores are mined, effective protective measures should be taken to minimize the amount of radiation exposure to staff. In mines with radioactive materials, ventilation facilities must be improved to reduce the concentration of radioactive materials and to ensure the safety of the working environment load radiation protection regulations. For workers exposed to carcinogenic compounds, various practical and effective labor protection measures must be taken to avoid or reduce the exposure to carcinogenic factors. A recent meta-analysis shows that indoor air pollution, including soot and cooking fumes, is also related to lung cancer development. Therefore, effective ventilation measures should be taken indoors to minimize the concentration of these fumes. 5.Living and eating habits Apart from staying away from cigarettes, it is also important to have healthy daily living and eating habits to prevent lung cancer. In life, you should eat less high-fat food, especially animal fat; eat less salt and less pickled food; do not eat food that has been stored at room temperature for too long and may be contaminated by fungus and other toxins. Preserve perishable food by refrigeration or other methods. Excessive or improper consumption of additives, contaminants and residues in food can be hazardous to health. Burnt food should be avoided, and fish, meat or bacon grilled directly on the fire should be consumed only occasionally. To rationalize the diet, plant-based vegetables such as vegetables, fruits, cereals and legumes account for more than 2/3. 6.Early diagnosis About 15% of lung cancer patients have no symptoms at all in the early stage, for the high-risk group, they should go to the hospital for physical examination regularly. If symptoms such as cough, hemoptysis, chest pain and fever appear, they should be taken seriously and go to the hospital for chest X-ray or CT examination in time. When lung cancer metastasizes to other organs, it is in advanced stage. Lung cancer often metastasizes to brain, bone, liver and adrenal gland. Once headache and back pain occur, it is important to pay attention to them and go to the hospital for examination in time to avoid delaying the disease.