Who Should Be Screened for Lung Cancer

NYU Langone’s Lung Cancer Screening Program follows the screening guidelines agreed upon by most professional medical organizations:

  • age 55 to 74
  • at least a 30 pack-year smoking history—equivalent to smoking one pack a day for 30 years or 2 packs per day for 15 years
  • a current smoker or have quit smoking within the last 15 years

Some groups also recommend screening for individuals over age 50 who have at least a 20 pack-year smoking history, if they have additional risk factors for lung cancer.

If a doctor recommends that you be screened, a low-dose CT scan is performed to look for any signs of early-stage lung cancer. 

However, it is important to keep in mind that not everyone should be screened. CT scans are very sensitive tests that can pick up many “false positives”—abnormalities in the lungs, including small scars or tiny lymph nodes, that are not cancer and are unlikely to ever cause a problem. 

When detected on a CT scan, such abnormalities may need further evaluation, which may cause anxiety. Evaluation may include follow-up CT scans or, infrequently, biopsies or other procedures for what usually proves to be a non-cancerous finding.

It is important to screen only individuals with an increased risk for lung cancer. 

What Increases Risk for Lung Cancer

The single most important risk factor for lung cancer is cigarette smoking. Tobacco use accounts for almost 90 percent of all lung cancers. So if you have ever smoked, you have an increased chance of developing lung cancer. The longer you smoke and the more packs of cigarettes you smoke, the greater your risk for developing cancer.

Other risk factors that may put you at increased risk for lung cancer include: 

  • exposure to radon, a radioactive gas that can exist in homes
  • exposure to asbestos, especially if exposure occurred in the workplace
  • significant exposure to second-hand smoke, either at home or at work
  • exposure to cancer-causing agents in the environment, especially occupational exposures
  • lung scarring from certain types of pneumonia or a diagnosis of chronic obstructive pulmonary disease (COPD) or emphysema
  • a first-degree relative, such as a parent or sibling, who has had lung cancer

Additional Considerations When Considering Screening 

Although the National Lung Cancer Screening Trial, a research study sponsored by the National Cancer Institute and published in 2011, showed that CT screening for lung cancer can save lives, many questions remain, such as who may benefit most from screening and how often should people be screened. The risk-benefit balance becomes increasingly unfavorable for individuals at lower risk for developing lung cancer, such as nonsmokers.

Some people undergo invasive diagnostic procedures as a result of lung cancer screening, and in some cases these tests lead to a diagnosis of cancer. In others, they confirm a benign condition. 

All invasive procedures performed based on the results of screening carry some risk of causing injury and even death, and the risks must be considered before deciding to undergo lung cancer screening.

You may also experience anxiety and concern resulting from false-positive tests, when a finding is identified on low-dose CT but proves not to be a cancer, as well as possible false security because of false-negative results. However, these issues have not yet been adequately studied.