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Lung Cancer Risks

Lung cancer kills more people than colon, breast, and prostate cancer combined. Yet there are ways to prevent lung cancer, the most important of which is to quit smoking. It is never to late to stop -- even for those who have incurable lung cancer, stopping smoking will improve the odds that therapy will work and prolong survival. 

Although smoking cessation is the best option to prevent the development of lung cancer, quitting does not eliminate the higher risk of lung cancer in former smokers, increasing the importance of lung cancer screening. While smoking is the most dangerous risk, other risks are also important.

Risk factors

Family history: Family history may increase a person’s risk of developing lung cancer and that risk multiplies if you are exposed to other risks, such as smoking.

If you have a family member who had lung cancer, you are as twice as likely to develop cancer as someone else without a family history of lung cancer. For people who have two or more first-degree relatives (brothers, sisters, parents, or children) who developed lung cancer, the chances of developing lung cancer are even higher. In families with a history of lung cancer, there is no such thing as a safe cigarette or a safe level of exposure to smoking.

Smoking: Smoking cigarettes is the top risk factor for developing lung cancer. In the United States, cigarette smoking causes approximately 85 percent of lung cancers. Smoking cigars and pipes also increases the risk of developing lung cancer. The more cigarettes and more years a person has smoked, the higher the risk.

The only way to decrease this risk is to quit smoking. Quitting decreases the risk, no matter how old you are or how many cigarettes you smoked. Smoking low-tar or low-nicotine tobacco products has not been shown to reduce the risk.

Secondhand smoke: Being exposed to secondhand smoke -- the smoke that comes from a burning cigarette or other tobacco product or that is exhaled by smokers – also increases the risk of developing lung cancer. Though it comes in smaller amounts, the same cancer-causing agents are inhaled through secondhand smoke.

Occupational exposure: Exposure to asbestos is known to cause mesothelioma. While it is no longer used, asbestos was commonly used in building materials and insulation. People who worked in construction, shipbuilding, certain types of manufacturing, firefighters, and other related fields may have been exposed to asbestos over the years of their employment. Of all mesothelioma cases reported, 70 to 80 percent have been linked to exposure to asbestos in the workplace.

Other toxins, such as arsenic, nickel, and chromium, as well as tar and soot, can also increase the risk of developing lung cancer, particularly for people who smoke. The risks of occupational exposures are increased for those who smoke.

Environmental exposure: Homes and offices may harbor chemicals or other substances that increase the risk of cancer for those who live or work in them. The biggest culprit is radon. In people who have never smoked, about 30 percent of deaths caused by lung cancer have been linked to being exposed to radon. Like occupational exposures, the risks of environmental exposure are increased for those who smoke.

Testing for radon is fairly simple to do, either by using a do-it-yourself radon test kit or by hiring a qualified tester. The Environmental Protection Agency lists where to find radon information in your area.

Vitamin supplements: It was once thought that vitamin supplements such as beta carotene could reduce the risk of lung cancer in heavy smokers. However, there is now substantial evidence that taking beta carotene supplements increases the risk of lung cancer, especially in smokers who smoke one or more packs a day. The risk is higher in smokers who have at least one alcoholic drink every day.

Reducing the risk

Because the risks of lung cancer can be reduced through screening, the Johns Hopkins Lung Cancer Program offers a Lung Cancer Screening/Pulmonary Nodule Clinic. People who are at high risk of lung cancer or who have had an abnormal finding on a chest X-ray or CT scan should be regularly screened to catch any changes before they become life-threatening.

Screening includes:

  • Meeting with a nurse practitioner during the first visit to provide personal history and determine the patient’s risk of developing lung cancer
  • Low-dose CT scans or other diagnostic procedures as necessary to detect lung cancer at its earliest and most curable stages.

The clinic’s team specializes in:

  • Personalized lung cancer risk assessment and recommendations for screening
  • Treatment plans for patients with lung nodules
  • Long-term nodule surveillance

Find out more

For an appointment and answers to your questions

As a leading treatment center for lung cancer, Johns Hopkins offers its patients personalized care, specialized treatment, and pioneering therapies to extend life.

To make an appointment or if you have questions, call 410-955-LUNG (5864).


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