Smoking, or exposure to tobacco in any form, is the major risk factor for both small cell and non-small cell lung cancer. Nonsmokers who breathe the smoke of others, often called secondhand smoke, are also at increased risk for these types of lung cancer.
If you do smoke, you can reduce your risk for lung cancer — and the risk for those around you — by stopping now. If you have been diagnosed with lung cancer or are undergoing chemotherapy, research also suggests that quitting smoking can improve the effectiveness of your treatment. Memorial Sloan Kettering offers a tobacco cessation program to help you to quit.
In some people, there is no identifiable cause of lung cancer. In fact, while smoking is the most significant risk factor, up to 20 percent of people with non-small cell lung cancer have never smoked.
Other risk factors include exposure to asbestos or radon, which causes damage to the lungs that can lead to cancer.
Doctors at Memorial Sloan Kettering have developed a lung cancer risk assessment tool that can be used to calculate an individual’s risk of developing lung cancer. This online questionnaire considers factors such as your age, gender, smoking history, and exposure to asbestos, and can be used to predict the likelihood of your developing lung cancer in the next ten years.
Knowing about your level of lung cancer risk can help you and your doctor make decisions about your healthcare, including whether to get screened for lung cancer.
Lung Cancer Screening
In November 2010 the National Cancer Institute released results of the National Lung Screening Trial, which showed that screening with low-dose CT (computed tomography) scans reduced the risk of death from lung cancer for individuals at high risk of getting the disease.
The results of this study do not mean that low-dose CT scans are for everyone. Test results can come back positive when there is no cancer present (called a false positive), leading to anxiety, unnecessary treatment, and possible complications.
Memorial Sloan Kettering recommends screening for lung cancer if you are between the ages of 55 and 74 and you have smoked the equivalent of at least one pack of cigarettes a day for 30 years, or 30 or more pack years. A pack year is a term used to describe the number of cigarettes a person has smoked over his or her lifetime. One pack year is defined as 20 cigarettes (one pack) smoked per day for one year.
Lung cancer screening is not a substitute for smoking cessation. Anyone considering screening who is still smoking should receive smoking cessation counseling.
For more detailed information about screening, see our screening guidelines for lung cancer.