Cells are the most basic functional units of the human body, and through the combination of individual cells they form organs with specific functions. For example, liver cells are responsible for liver metabolism, pancreatic cells are responsible for pancreatic juice secretion, and skin epithelial cells are responsible for protection. The human body is amazing in that various cells grow and differentiate according to their functional needs. Cells also age and die, and in order to maintain the body’s function, new cells are constantly generated and differentiate into functional, mature cells. This cellular cycle of life, death and aging is extremely orderly. When the process of cell division and proliferation is faulty or abnormal, it will cause serious consequences. Normal cell proliferation takes place according to the needs of the body, but when this process of self-renewal becomes uncontrolled, the cells can overgrow and even invade other surrounding organs. When this abnormal proliferation forms a certain size or even a visible mass, it is called a “tumor”. Some tumors are benign and not life-threatening, they do not directly invade the surrounding organs and do not metastasize to distant places, therefore, many benign tumors do not require treatment. However, if the tumor can obviously invade the surrounding organs and spread to distant places, or even have the possibility of recurrence after being removed, we call it malignant tumor, which is also known as “cancer” in common parlance. Lung cancer is a tumor formed when cells in the lung become malignant and proliferate abnormally. These cells can originate from the bronchi, bronchoalveoli, and alveoli, or even from the trachea. However, as lung cancer grows, it gradually impairs the patient’s lung function, producing a number of symptoms such as breathing problems, hemoptysis, coughing, and pain. Because of the large size of the lung, it is difficult to be detected in the early stage of lung cancer, and even when distant metastasis has occurred, patients are still unaware of it. Of course, many patients do not have the awareness of vigilance, even if they have the manifestation of coughing and coughing sputum, and mistake it for general cold or bronchitis. Therefore, when lung cancer patients visit the doctor because of symptoms, the tumor has often grown very large and even extra-pulmonary metastasis has already occurred. Many patients come to the clinic because of headache symptoms after brain metastasis. Lung cancer can metastasize to other parts of the body through the lymphatic and blood systems. If we look at the statistics of lung cancer in previous years, it is enough to make our jaws drop. Lung cancer has now become one of the most important public health problems that endanger human health. According to the World Health Organization (WHO) report in 2008, 7.6 million people died of tumors worldwide that year, accounting for 13 percent of all deaths. Among them, 1.37 million deaths from lung cancer ranked first, 730,000 from stomach cancer, 690,000 from liver cancer, 600,000 from colorectal cancer, and 450,000 from breast cancer. According to the estimation of environmental and other risk factors and the proportion of cases occurring each year, the number of people dying from tumors will reach 13 million each year by 2030. The mortality rate of lung cancer in China in the 1970s was 5.74/100,000, and the worldwide average was 7.41/100,000, ranking after gastric cancer, esophageal cancer, liver cancer and cervical cancer in the classification of causes of death from malignant tumors. However, by 2002, lung cancer had become the number one cause of death in 14 counties and cities nationwide. The National Center for Disease Control and Prevention (NCDC) reported in 2012 that lung cancer has become the number one total mortality Liu in China, ranking first for both men and women (30.61/100,000 overall, 41.14/100,000 for men and 19.63/100,000 for women). Considering the rising trend of lung cancer incidence and overall environmental conditions in China in recent years, the incidence and mortality rate of lung cancer in China will definitely exceed that of the United States. Lung cancer is one of the malignant tumors with the worst prognosis. Less than 15% of all lung cancer patients diagnosed clinically are able to live to 5 years. In stark contrast, 88% of breast cancer patients survive beyond 5 years with treatment, and the 5-year survival rate for prostate cancer is almost 99%. Lung cancer is more common in older populations, and among men, it becomes the number one cause of cancer death after age 40. Among women, lung cancer surpasses breast cancer as the number one cause of death after age 60. In the United States, the incidence of lung cancer has steadily declined in recent years, from 102/100,000 in 1984 to 73/100,000 in 2005 for men, and is not increasing for women. This is mainly related to the significant and sustained decline in the number of smokers in the United States after 1970. In particular, the number of men who smoke has declined significantly. Lung cancer has become a worldwide health problem, and countries are working tirelessly to reduce the incidence of lung cancer and reduce risk factors. Tobacco use is undoubtedly the most abhorrent lung cancer yeast, and now that China has become the world’s largest consumer of tobacco production, the resulting lung cancer and other related diseases are bound to have an explosive increase in the next 20 years.