Lung Cancer - Non-Small Cell: Risk Factors and Prevention

Aprobado por la Junta Editorial de Cancer.Net, 12/2022

ON THIS PAGE: You will find out more about the factors that increase the chance of developing non-small cell lung cancer (NSCLC). Use the menu to see other pages.

A risk factor is anything that increases a person’s chance of developing cancer. Although risk factors often influence the development of cancer, most do not directly cause cancer. Some people with several risk factors never develop cancer, while others with no known risk factors do. Knowing your risk factors and talking about them with your doctor may help you make more informed lifestyle and health care choices. NSCLC occurs most often in people who smoke or in those who have smoked in the past. However, people who don’t smoke can also develop NSCLC, so it is important for all people to learn about the risk factors and signs and symptoms of NSCLC.

The following factors may raise a person’s risk of developing NSCLC:

  • Tobacco and smoking. Tobacco smoke damages cells in the lungs, causing the cells to grow abnormally. The risk that smoking will lead to cancer is higher for people who smoke heavily and/or for a long time. Regular exposure to smoke from someone else’s cigarettes, cigars, or pipes can increase a person’s risk of lung cancer, even if that person does not smoke. This is called Environmental Tobacco Smoke (ETS) or “secondhand” tobacco smoke.

    Smoking marijuana and using electronic cigarettes may also increase the risk of lung cancer, but the actual risk is unknown.

  • Asbestos. These are hair-like crystals found in many types of rock and are often used as fireproof insulation in buildings. When asbestos fibers are inhaled, they can irritate the lungs. Many studies show that the combination of smoking and asbestos exposure is particularly dangerous. People who work with asbestos in a job such as shipbuilding, asbestos mining, insulation, or automotive brake repair and who smoke have a higher risk of developing NSCLC. Using protective breathing equipment reduces this risk.

  • Radon. This is an invisible, odorless gas naturally released by some soil and rocks. Exposure to radon has been associated with an increased risk of some types of cancer, including lung cancer. Most hardware stores have kits that test home radon levels, and basements can be ventilated to reduce radon exposure.

  • Air pollution. Research has found that exposure to outdoor air pollution can lead to lung cancer. Almost everyone lives in a place where they are regularly exposed to air pollution. Common causes of pollution include transportation and industrial fumes, power generation, and smoke from intentional burning and wildfires. People with a history of smoking tobacco products are at an even higher risk. You can reduce some of your exposure by checking the air pollution forecast for your area and avoiding outdoor exercise when levels are high.

  • Other substances. Other substances such as gases or chemicals at work or in the environment can increase a person’s risk of developing lung cancer. In some parts of the world, people exposed to cooking flames from coal or wood might increase risk of lung cancer. Also, fumes from diesel gas or from soldering metals could increase the risk of lung cancer. Other factors that may increase the risk of lung cancer include exposure to radiation, arsenic, nickel, and chromium.

  • Genetics. Some people have a genetic predisposition for lung cancer. Even if they never smoke cigarettes, people with a parent, brother, or sister with lung cancer could have a higher risk of developing lung cancer themselves due to genetic changes. Research about inherited genetic mutations and lung cancer is ongoing.


Different factors cause different types of cancer. Researchers continue to look into what factors cause NSCLC, including ways to prevent it. Although there is no proven way to completely prevent NSCLC, you may be able to lower your risk. Talk with your health care team for more information about your personal risk of cancer.

The most important way to prevent lung cancer is to avoid tobacco smoke. People who never smoke have the lowest risk of lung cancer. But even people who have smoked a long time can reduce their risk of lung cancer by stopping smokingLearn more about the health benefits of quitting smoking.

Attempts to prevent lung cancer with vitamins or other treatments have not worked. For instance, beta-carotene, a drug related to vitamin A, has been tested for the prevention of lung cancer. It did not reduce the risk of cancer. In people who continued to smoke, beta-carotene actually increased the risk of lung cancer.

The next section in this guide is ScreeningIt explains how tests may find cancer before signs or symptoms appear. Use the menu to choose a different section to read in this guide.