Screening Low-Risk Individuals for Lung Cancer: The Need May Be Present, but the Evidence of Benefit Is Not

Abstract

Worldwide, lung cancer is the most common killer among cancers, advanced disease has worse outcomes, earlier stage detection leads to better outcomes, and high-quality screening has a favorable net benefit. With the mortality reduction recognized from annual low-radiation dose computed tomography by screening those at high risk, there has been consideration that this benefit could translate to those who have never smoked. There have been several large-scale, single-arm, observational trials in Asia in persons with light to no smoking histories, with or without a family history of lung cancer, which have revealed high or higher lung cancer detection rates than previously reported in high-risk persons who currently or formerly smoked. The Early Detection Program for Lung Cancer in Taiwan, of nearly 50,000 persons, revealed that the cancer detection rate for those screened with low-radiation dose computed tomography was more than twofold higher in light- or never-smokers with a family history of lung cancer compared with high-risk persons with more than 30 or more pack-years exposure and meeting U.S. Preventative Services Task Force criteria for screening. In addition, more than 90% of the cancers detected in those with a family history were in early stage. On the basis of those findings, the researchers concluded that screening first-degree relatives of those with a family history of lung cancer, irrespective of smoking history, would lead to a decrease in lung cancer mortality. We believe that the findings in this cohort and others like it represent substantial overdiagnosis and that the harms associated with screening a population that has a low likelihood of developing lethal cancers have not been thoroughly considered. Here, we provide our perspective and consider the potential benefits and harms of screening populations outside those currently eligible using the U.S. Preventative Services Task Force criteria.

Keywords: Family history; Lung cancer; Never smokers; Overdiagnosis; Screening.