Causes of peripheral lung cancer

What is the cause of peripheral lung cancer? The so-called peripheral lung cancer is actually also called lung field lung cancer. It refers to lung cancer that occurs in the bronchi below the lung segments and in the small bronchi. It is characterized by late onset of clinical symptoms and a slow spread, which can cause patients to experience severe breathing difficulties.

What are the causes of peripheral lung cancer?

1. Smoking Smoking is currently considered to be the most important high-risk factor for lung cancer. Tobacco contains more than 3,000 chemical substances, among which polycyclic aromatic hydrocarbons (such as benzopyrene) and nitrosamines have strong carcinogenic activity. Polycyclic aromatic hydrocarbons and nitrosamines can cause DNA damage to bronchial epithelial cells through various mechanisms, activating oncogenes (such as Ras genes) and inactivating tumor suppressor genes (such as p53, FHIT genes, etc.), thereby causing cell transformation and ultimately cancer.

2. Occupational and environmental exposure Lung cancer is the most important type of occupational cancer. It is estimated that about 10% of lung cancer patients have a history of environmental and occupational exposure. It has been proven that the following 9 occupational environmental carcinogens increase the incidence of lung cancer: byproducts of aluminum products, arsenic, asbestos, bis-chloromethylether, chromium compounds, coke ovens, mustard gas, nickel-containing impurities, and vinyl chloride. Long-term exposure to substances such as beryllium, cadmium, silicon, and formalin will also increase the incidence of lung cancer. Air pollution, especially industrial waste gas, can cause lung cancer.

3. Ionizing radiation The lungs are an organ that is more sensitive to radiation.

4. In patients with previous chronic lung infections such as tuberculosis, bronchiectasis, etc., the bronchial epithelium may metaplasia into squamous epithelium and cause cancer during the chronic infection, but this is relatively rare.

5. Genetic factors Family clustering, genetic susceptibility, reduced immune function, metabolic and endocrine dysfunction, etc. may also play an important role in the occurrence of lung cancer. Many studies have shown that genetic factors may play an important role in people and/or individuals who are susceptible to environmental carcinogens.

6. Air pollution The high incidence of lung cancer in developed countries is mainly due to the pollution of the atmosphere by harmful substances such as benzopyrene carcinogenic hydrocarbons produced by the combustion of oil, coal and internal combustion engines and asphalt road dust in industrial and transportation-developed areas. Air pollution and smoking may promote each other and play a synergistic role in the incidence of lung cancer.