An Opportunity to Reduce Disparities in Lung Cancer Screening

Based on the 2021 update of the US Preventive Services Task Force (USPSTF) lung cancer screening criteria, the study by Ritzwoller et al¹ estimated the population-level changes in screening eligibility by sex, race and ethnicity, sociodemographic factors, and comorbidities using the electronic health records of 5 community-based health care systems. When applying the 2021 USPSTF criteria, the authors found an additional 18 533 individuals, or a 53.7% relative increase from the 2013 criteria, among those who were eligible for lung cancer screening from January 1, 2010, to September 30, 2019.¹ Along with identifying populations who are newly eligible for lung cancer screening, the updated USPSTF criteria were associated with an increased proportion of women, racial and ethnic minority groups, those with lower comorbidity burden, and those with low socioeconomic status being eligible for screening. Accordingly, wider screening was associated with an estimated 30% increase in lung cancer diagnosis.¹

Previous studies have indicated that modification of the 2013 USPSTF criteria would result in more equitable lung cancer screening eligibility for individuals of different races, ethnicities, and incomes.² Ritzwoller et al¹ further demonstrated that the 2021 USPSTF criteria were associated with greater benefits to previously underrepresented populations. Specifically, the male to female ratio for lung cancer screening eligibility decreased to 52.2% male and 47.8% female from the previous ratio of 54.4% male to 45.6% female, and the proportion of women being diagnosed with lung cancer now exceeded that of men, reaching 52.4%.¹ In addition, the lung cancer screening eligibility increased by 11.5% for Asian, Native Hawaiian, or Pacific Islander, 18.3% for Hispanic, and 20.7% for non-Hispanic Black individuals compared with the increase among non-Hispanic White individuals.¹ Furthermore, under the 2021 USPSTF criteria, lung cancer screening among those with lower socioeconomic status increased proportionally.¹ The authors’ findings indicated that implementation of the 2021 USPSTF criteria has the potential to reduce the disparities in lung screening eligibility according to race and ethnicity, sex, or sociodemographic factors.

The 2021 USPSTF criteria are expected to lead to screening of younger individuals with fewer comorbid conditions. Ritzwoller et al¹ estimated a 3.6% reduction (from 22.4% under the 2013 criteria to 18.8% under the 2021 criteria) in the prevalence of chronic obstructive pulmonary disease (COPD) among the individuals who are eligible under the 2021 USPSTF criteria. The prevalence of COPD increases with age and reaches its peak among those 75 years or older.³ In the study by Ritzwoller et al,¹ more patients among the newly eligible population aged 50 to 54 years, which accounts for 31.5% of the total newly eligible patients, have not yet developed COPD. In addition, previous studies also indicated that the lung cancer screening eligibility guidelines that use the 30–pack-year criterion exclude high-risk light smokers.⁴ Therefore, further studies are necessary to identify the implication of the minimum smoking history under the 2021 USPSTF criteria for the incident detection of COPD.

Ritzwoller et al¹ found that, under the USPSTF-21 criteria, the detection of individuals with incident lung cancer increased in all populations by race and ethnicity. In addition, the diagnosis of incident lung cancer in women and those with lower socioeconomic status accounted for a larger proportion of detected lung cancers than those detected under the 2013 USPSTF criteria. Given the disparities in lung cancer screening eligibility according to race and ethnicity, sex, or socioeconomic status,⁵ the updated USPSTF criteria may help alleviate concerns that current screening guidelines overlook vulnerable populations with a disproportionate lung cancer burden.

The approach by Ritzwoller et al¹ to use health care systems’ electronic health records to estimate the clinical impact associated with lung cancer screening eligibility changes holds promise for estimating the value of the 2021 USPSTF criteria in different populations and revealing the potential of the updated guidelines to benefit underrepresented populations. The findings of this study may further support individual lung cancer screening decisions. Furthermore, estimating the consequences of using the 2021 USPSTF criteria could enable different countries and regions to develop better lung cancer screening programs. For example, the 2021 USPSTF criteria are now more similar to the national guidelines for annual lung cancer screening in China, which recommend low-dose computed tomography for high-risk individuals aged 50 to 74 years with at least a 20 pack-year smoking history and who currently smoke or have quit within the past 5 years.⁶ The method used by Ritzwoller et al¹ of estimating the change in lung cancer screening eligibility by sex and sociodemographic factors may help in the evaluation of benefits in specific population categories in China. In the United Kingdom, a lung cancer screening trial in individuals aged 50 to 75 years classified high-risk participants as current smokers or ex-smokers, and several lung cancer screening programs have been implemented.⁷

Identifying lung cancer screening eligibility using available electronic health records in health care systems may provide guidance for designing future large-scale screening programs. Given that lung cancer kills more than 1.7 million individuals worldwide annually,⁸ screening guidelines that improve outcomes while reducing disparities are needed to address this pressing public health issue.

Published: October 12, 2021. doi:10.1001/jamanetworkopen.2021.29126

Open Access: This is an open access article distributed under the terms of the CC-BY License. © 2021 Song J et al. JAMA Network Open.

Corresponding Author: Jiangdian Song, PhD, College of Health Management, China Medical University, No. 77, Puhe Rd, Shenbei New District, Shenyang, Liaoning, 110122, China (song.jd0910@gmail.com).

Conflict of Interest Disclosures: None reported.