Study Reveals Racial Inequity in Lung Cancer Screening Based on Pack-Year Smoking History

Pack years, which are the equivalent of smoking one pack of cigarettes a day for one year, may be a flawed measure of cumulative tobacco exposure.

What’s more, many believe using pack-years to determine eligibility for lung cancer screening eligibility excludes high-risk individuals, most notably people from certain racial or ethnic minority groups.

A collaboration between researchers at Massachusetts General Hospital, Boston University, Vanderbilt University Medical Center and the University of Chicago Hospital, explored whether how using a smoking duration cutoff instead of a pack-year one to determine lung cancer screening eligibility would affect the populations eligible for lung cancer screening.

Their results were published in the Journal of Clinical Oncology in the spring of 2024, and the further study is currently being conducted according to its authors.

Alexandra L. Potter

To see if their hypothesis was valid, lead author Alexandra L. Potter, a clinical research coordinator at Massachusetts General Hospital and president of the American Lung Cancer Screening Initiative, and her colleagues analyzed data from almost 50,000 individuals with a smoking history from the Southern Community Cohort Study (SCCS) and approximately 22,000 other individuals with a smoking history from the Black Women’s Health Study (BWHS). The study authors assessed eligibility for screening under the current United States Preventive Services Task Force guideline of 20 or more pack years with a proposed replacement of 20 or more years of smoking.

The results for the SCCS cohort showed that 57.6% of Black patients with lung cancer would have qualified for screening compared with 74% of White patients with lung cancer using the current guidelines. Switching to smoking duration raised the percentages to 85.3% and 82%, respectively.

Using duration instead of pack year produced similar results in the BWHS cohort.

“Use of a 20-year smoking duration cutoff instead of a 20-pack-year cutoff greatly increases the proportion of patients with lung cancer who would qualify for screening and eliminates the racial disparity in screening eligibility between Black versus White individuals,” Potter and her collaborators concluded.

Additionally, they noted that looking at smoking duration has further benefits, such as being easier to calculate and being a more precise assessment of smoking exposure.