Association of Race With Lung Cancer Risk Among Adults Undergoing Lung Cancer Screening

This cross-sectional study examines whether race is associated with differences in 6-year lung cancer risk among patients eligible for US Preventive Services Task Force–recommended lung cancer screening.


Introduction
African American individuals at high risk of lung cancer may experience greater mortality benefit from annual lung cancer screening (LCS) compared with White individuals. 1,2 However, African American individuals develop lung cancer with fewer pack-years of smoking and at younger ages than White individuals, and they are less often eligible for LCS when using United States Preventive Services Task Force (USPSTF) criteria. 3 One approach to mitigate disparities in LCS eligibility is to use lung cancer risk prediction models to identify the patients with the highest risk. 4 The Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial modified logistic regression model for lung cancer prediction (PLCOm2012) may improve sensitivity in lung cancer detection, specifically among African American individuals, and potentially reduce underrepresentation in screening cohorts. 5 This study aimed to identify differences in PLCOm2012 6-year lung cancer risk among USPSTF-eligible LCS patients.

Methods
The Thomas Jefferson University institutional review board approved this cross-sectional study and granted a waiver of informed consent because of the minimal risk nature of the research. This study followed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) reporting guideline.
The Jefferson LCS Program is a centralized program at an urban, academic medical center.
Sociodemographic and clinical data from patients screened from January 2018 to September 2020 were extracted from the LCS Registry. This included lung cancer risk using the PLCOm2012 model, calculated at entry into LCS, and diagnosis of screen-detected lung cancer. 6 After excluding patients who self-reported races other than African American or White, risk quartiles were generated using median PLCOm2012 risk values for the screening and cancer cohorts. Descriptive statistics, independent t tests, χ 2 tests, and Mann-Whitney U tests were performed using a P < .05 significance threshold. Statistical analyses were 2-sided and conducted using SPSS statistical software version 26 (IBM Corp) from October 5 to November 11, 2020.

Discussion
To our knowledge, this study is the first to measure PLCOm2012 lung cancer risk among screened individuals and include more than 40% African American participants. We found that lung cancer risk scores were not aligned with lung cancer diagnoses in African American patients. In fact, African American individuals with screen-detected lung cancers were clustered predominantly in the lower risk quartiles. However, among White individuals undergoing screening, higher risk scores were associated with lung cancer diagnoses.
Our findings suggest that we should use caution in applying risk models to diverse populations, given that our current understanding of lung cancer risk is incomplete. Existing models have been derived from screening trials including 5% or fewer African American individuals and may not apply equitably to real-world screening participants. 2,4 Although our study is limited by its single-center approach and short duration of follow-up, the racially diverse patient population allowed us to identify weaknesses in risk calculation. Determinants of health, including social constructs and environmental factors, may be critical moderators of lung cancer risk among underserved