Screening Could Reduce Lung Cancer Mortality

Screening for lung cancer with low-dose computed tomography (LDCT) in all screening-eligible current and former smokers could potentially avert approximately 12,000 lung cancer deaths each year in the United States, according to the results of a study published early online in the journal Cancer.[1]

Lung cancer is the leading cause of cancer death among both men and women in the United States. The disease is often detected at an advanced, difficult-to-treat stage.

Cancer screening involves the use of tests to detect cancer at an early stage in people who don’t have any symptoms of the disease. For cancers such as breast cancer, colorectal cancer, and cervical cancer, screening has contributed to decreased rates of cancer death. However, early detection of lung cancer has proven more difficult. In order for new screening methods to be adopted into routine clinical care, the measures must identify cancer early enough to improve outcomes, must be economically feasible, and must detect cancer with an acceptable degree of accuracy.

Low-dose CT scans are a special type of imaging scan that can identify smaller nodules than chest x-rays, making them a strong candidate for lung cancer screening. Although low-dose CT scans can detect lung cancer early, they also can have false-positive results, which means they may not be appropriate for standard use because false-positive results can lead to unnecessary invasive procedures that can have deadly complications. However, in high-risk populations—such as older individuals who are current or former smokers—the benefits of screening with low-dose CT scans may outweigh the harms.

The most recent lung cancer screening guidelines state that smokers and former smokers ages 55 to 74 who have smoked for 30 pack years or more and either continue to smoke or have quit within the past 15 years should undergo annual screening with low-dose CT scan.[2] The National Lung Screening Trial (NLST) conducted from 2002 through 2009 found that, compared with chest x-ray, low-dose computed tomography screening reduces lung cancer deaths by about 20 percent among this population.

Using information from the NLST study and data regarding the US population size, researchers concluded that in 2010, approximately 8.6 million Americans were eligible for lung cancer screening with low-dose computed tomography according to the criteria used in the trial. When they combined this data with information on lung cancer death rates, they estimated that if all screening-eligible Americans were to receive low-dose computed tomography screening, approximately 12,000 lung cancer deaths would be delayed or prevented each year in the United States.

The researchers concluded that lung cancer screening with low-dose computed tomography among screening-eligible current and former smokers could potentially avert a large number of lung cancer deaths each year. More research is needed to determine the benefits of lung cancer screening with low-dose computed tomography.

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