Causes of Lung Cancer
Researchers have found a link between lung cancer and exposure to certain air pollutants, such as by-products of the combustion of diesel and other fossil fuels. However, this relationship has not been clearly defined, and more research is being done to determine if this is a true cause of lung cancer.
Certain lung diseases, such as tuberculosis (TB), increase a person's chance of developing lung cancer. The disease tends to develop in areas of the lung that are scarred from TB.
A person who has had lung cancer once is more likely to develop a second lung cancer, compared with a person who has never had the disease. Quitting smoking after lung cancer is initially diagnosed may prevent the development of a second lung cancer.
Researchers continue to study the causes of lung cancer and to search for ways to prevent it. We already know that the best way to prevent lung cancer is to quit (or never start) smoking. The sooner a person quits smoking, the better. Even if you have been smoking for many years, it's never too late to benefit from quitting.