Improving Equity in Lung Cancer Screening Eligibility

According to U.S. Preventive Services Task Force recommendations and insurance requirements, eligibility for lung cancer screening by computed tomography requires ≥20 pack-years of smoking (NEJM JW Gen Med Apr 15 2021 and JAMA 2021; 325:962). Pack-year calculations combine “smoking intensity” (number of cigarettes daily) with smoking duration; however, we don't know if pack-years are a better marker for lung cancer risk than is smoking duration alone. This issue has relevance for racial disparities in the U.S.: Black patients, who tend to have lower smoking intensity than white patients, are less likely to qualify for screening and more likely to have advanced-stage lung cancers at diagnosis.

In this retrospective U.S. study, researchers analyzed two large cohorts with data on smoking history and incidence of lung cancer. The hypothetical performance of the standard ≥20-pack-year screening criterion was compared with a proposed ≥20-year smoking-duration criterion.

Among patients in one cohort who eventually developed lung cancer, 58% of Black patients and 74% of white patients would have qualified for screening under the pack-year criterion. These proportions increased to 85% and 82%, respectively, under the smoking-duration criterion, which is a substantial improvement in sensitivity and eliminates the racial disparity. In the second cohort (comprised exclusively of Black patients), a smoking-duration criterion would have been more sensitive for predicting eventual lung cancer.