The current situation of lung cancer incidence Due to the development of industry, the incidence of lung cancer in China is on the rise year by year. According to the information provided by the National Cancer Prevention and Treatment Research Office of the Ministry of Health, the number of lung cancer cases in China has increased by 120,000 between 2000 and 2005, from 260,000 in 2000 to 330,000 in 2005 for men, an increase of 26.9%; and from 120,000 to 170,000 for women. According to epidemiological experts, if smoking and air pollution are not controlled, by 2025, China will have more than 1 million lung cancer patients each year, becoming the world’s number one lung cancer country, especially in cities such as Beijing, Shanghai, Hefei, Nanjing, and of course, Sichuan and Chengdu are no exception. Causes of lung cancer Smoking: has been recognized as the most important risk factor for lung cancer. 1992 International Conference on Lung Cancer concluded that the relationship between lung cancer and smoking needs no further study. 1996 WHO annual report pointed out that 85% of male lung cancer patients and 46% of female lung cancer patients worldwide are smoking-related. The incidence of lung cancer is 200-500 times higher in smokers than in non-smokers, with the difference becoming more significant with age, and at age 60, the correlation can be as high as 100 times. In the United States, 85%-90% of the 135,000 annual deaths from lung cancer are related to smoking. China – serious: 300 million smokers, 400 million passive smokers. In 1996, the national smoking rate was 37.62% and 66.9% for men. Now, 63%, the regular smoking rate reached 61.4%. The age of smoking has increased from 22.4 years in 1984 to 19.7 years, and the daily smoking has increased from 13 to 15 cigarettes. The smoking rate for women is 4.2%, now 3.8% and 3.4% for regular smokers, and the age of starting smoking is 5 years later than for men. Surveys conducted in Liaoning, Shanghai, and Beijing showed that smoking accounted for 55%-81% of the causes of lung cancer in men and 24%-41% of the causes of lung cancer in women. The relationship between smoking and lung cancer risk is related to the type of tobacco, age of smoking initiation, years of smoking and the amount of smoking. The risk for cigarette smoking is 9.0 and for cigar or pipe smoking 2.9 and 2.5. The risk for lung cancer is higher for those who smoke without a filter and with a high tar content than for those who smoke with a filter and a low tar content. Smokers tend to have more squamous cancers. There are benefits to quitting smoking, with a relative risk of 1.1 for men who have quit smoking for 10 years or more.