Lung Cancer Causes - An Overview

What Causes Lung Cancer?

There are many lung cancer causes, in addition to the well-known link with smoking. Lung cancer, and cancer in general, is most often a “multifactorial” disease, that is, many factors work together to cause or prevent cancer. An overview of common lung cancer causes includes:

Lifestyle Lung Cancer Causes

• Smoking – Smoking is responsible for 87% of lung cancers.
• Lack of exercise – People who engage in moderate exercise are less likely to develop lung cancer.
• Unhealthful diet – A higher intake of foods, such as salads, is associated with a lower risk of developing lung cancer.
• Excess alcohol – An excess intake of alcohol may raise the risk of lung cancer in smokers.

Environmental Lung Cancer Causes

• Radon – Radon is the second-leading cause of lung cancer, following smoking, and the leading cause of lung cancer in nonsmokers.
• Asbestos – Exposure to asbestos is responsible for the majority of mesothelioma, a rare tumor involving the lining of the lungs.
• Secondhand smoke – Secondhand smoke increases the risk of lung cancer in nonsmokers two- to- three-fold.
• Air pollution – Pollution, especially in urban areas, appears to raise the risk of lung cancer.
• Industrial chemicals – Several chemicals used in commerce are linked with a higher risk of lung cancer.
• Radiation – Atomic bomb survivors have an elevated risk of developing lung cancer, as do those who have undergone radiation therapy for other types of cancer, such as Hodgkin’s disease.

Occupational Lung Cancer Causes

Occupational exposure to carcinogens is estimated to be responsible for 13 to 29% of lung cancers in men.

Other Lung Diseases as Lung Cancer Causes

People who suffer from Chronic Obstructive Pulmonary Disease (COPD) have an elevated risk of developing lung cancer irrespective of smoking history.

Genetic Lung Cancer Causes

In general, a genetic predisposition to lung cancer does not mean someone will develop lung cancer. It means they are more likely to develop lung cancer, especially when combined with other risk factors. Research looking at the role of heredity in the development of lung cancer is in its infancy, but researchers are beginning to isolate some of the genetic changes that are associated with an increased risk of lung cancer.

Infectious Lung Cancer Causes

Research looking at infectious diseases as a possible cause of lung cancer is also in its infancy. Infectious agents that have been associated with lung cancer in newer studies include: chlamydia pneumoniae, Human Papilloma Virus (HPV) and measles.

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