Analysis of the 30-Pack-Year Smoking Threshold in African Americans From an Underserved Lung Cancer Screening Program

African Americans were underrepresented in lung cancer screening (LCS) trials, despite having higher lung cancer incidence and worse outcomes compared with Caucasians. There is concern that the 30-pack-year threshold excludes some African Americans who may benefit from LCS.

LCS in an underserved health care system was reviewed. Providers attested that patients met LCS criteria, including 30-pack-year history, but patients also self-reported smoking histories. Self-reported data were used to identify patients with <30-pack-year histories.

Over 2 years, 784 patients self-reported sufficient data to calculate pack-years. The majority were men (57.5%), and 66.2% were African Americans. Median total years smoked was 40 (interquartile range, 30-45 years), and median pack-years was 25 (interquartile range, 15-40 pack-years). African Americans were more likely to report <30 pack-years compared with other races (P < .001). The overall incidence of lung cancer was 2.0%, and incidence was similar for those with ≥30 or <30 pack-years (2.1% versus 2.0%; odds ratio, 0.94; 95% confidence interval, 0.35-2.53; P = .902). Race was not associated with lung cancer diagnosis, but African Americans were the only race to have lung cancer if pack-years were <30. The incidence of cancer in African Americans was similar in those who reported ≥30 or <30 pack-years (2.2% versus 2.7%; odds ratio, 1.21; 95% confidence interval, 0.39-3.75; P = .740), and the 30-pack-year threshold was not associated with lung cancer diagnosis.

This is the first review of LCS in African Americans who self-reported <30 pack-years. Although retrospective, these data raise concern that the 30-pack-year threshold may not be an appropriate LCS criterion in African Americans.