Lowering the United States Preventive Services Task Force (USPSTF) smoking pack-year criteria to a minimum 20-pack-year history was associated with increased lung cancer screening eligibility among African American smokers, according to the results of a study published in JAMA Oncology.
Lung cancer incidences and eligibility of screening from current as well as former smokers in adults visiting community health centers across 12 southern US states were analyzed and compared between groups. The rates of cancer and screening eligibility were compared between African American and white participants.
Among 48,364 ever smokers, 32,463 (67%) were African American and 15,901 (33%) were white, with 1269 incident lung cancers identified. Of all the study participants, 17% of African American smokers were eligible for USPSTF screening compared with 31% of white smokers. Among persons diagnosed with lung cancer, a significantly lower percentage of African American smokers was eligible for screening compared with white smokers (32.2% vs 56.5%%; P <.001). The main difference for this disparity was the fewer smoking pack-years among African American smokers (median pack-years, 25.8 vs 48.0, respectively; P <.001). If the current criteria were revised to a minimum 20-pack-year smoking history, it would improve the sensitivity of the screening test to 49.0% in a 55-year-old African American current smoker, but it would decrease the specificity to 71.6%.
Researchers also noted an inverse association between age at diagnosis and stage of lung cancer in both African American smokers and white smokers. “These data provide additional evidence that reducing the minimum screening age to 50 years may allow greater detection of disease at preclinical early stage for African American individuals, assuming a 3- to 6-year progression of disease from stage 1A to IV,” they wrote.
There were several limitations to this study, including self-reported smoking data, lack of information on actual lung screening use, and missing data on smoking and race for 5566 participants.
“[R]ace-specific adjustment of pack-year criteria in lung cancer screening guidelines would result in more equitable screening for African American smokers at high risk for lung cancer,” the researchers concluded.
Aldrich MC, Mercaldo SF, Sandler KL, Blot WJ, Grogan EL, Blume JD. Evaluation of USPSTF lung cancer screening guidelines among African American adult smokers [published online June 27, 2019]. JAMA Oncol. doi:10.1001/jamaoncol.2019.1402