What causes tumors? It is often related to three factors.

Clinically, if tumor diseases become malignant, it is easy to cause cancer in people's bodies. So, how are tumors caused?

1. Smoking:

Long-term smoking can cause proliferation of bronchial mucosal epithelial cells, induce squamous cell carcinoma or undifferentiated small cell carcinoma. Although non-smokers can also develop lung cancer, adenocarcinoma is more common. Cigarettes release carcinogens when they burn.

2. Occupational factors:

Long-term exposure to radioactive substances such as uranium and radium and their derivatives, carcinogenic hydrocarbons, arsenic, chromium, nickel, copper, tin, iron, coal tar, pitch, petroleum, asbestos, mustard gas and other substances can induce lung cancer, mainly squamous cell carcinoma and undifferentiated small cell carcinoma.

3. Chronic lung diseases:

For example, tuberculosis, silicosis, pneumoconiosis, etc. can coexist with lung cancer. The incidence of cancer in these cases is higher than that of normal people. In addition, chronic inflammation of the lungs and bronchi and pulmonary fibrosis and scar lesions may cause squamous metaplasia or hyperplasia during the healing process. On this basis, some cases can develop into cancer.