What Are the Causes of Bronchial Carcinoma?

Bronchial carcinomas are lung cancers that begin in the tissues of the bronchi, or breathing tubes, inside the lungs. Doctors have identified a number of causes and risk factors for these diseases.

The Facts

• According to the University of Maryland Medical Center (UMMC), more than 95 percent of all lung cancers are bronchogenic, meaning that they begin in the bronchi.

Smoking

• Roughly 85 to 90 percent of all lung cancers result from cigarette smoking. Chances of cancer development increase with the number of cigarettes a person smokes, as well as the number of years, reports the Merck Manuals Online Medical Library.

Additional Risk Factors

• The UMMC lists additional risk factors for lung cancer that include exposure to second-hand smoke, smoking marijuana, repeated inflammation from tuberculosis or pneumonia, family history and exposure to asbestos or industrial grade talc that may also contain asbestos.

Radon Gas

• The U.S. Environmental Protection Agency (EPA) also cites home exposure to radon gas—a byproduct of the breakdown of uranium—as a major source of lung cancer, causing roughly 21,000 deaths each year.

Considerations

• Individuals who stop smoking lower their chances of developing lung cancer. However, their risks will always remain higher than those for individuals who have never smoked.