High Adherence Over a Decade of Annual Lung Cancer Screening in an Occupational Cohort

Adherence to an annual low-dose chest CT (LDCT) scan regimen is essential to lung cancer screening success but has been scarcely studied beyond 2 annual CT scans.

From 2014 to 2024, we conducted annual LDCT screening for 1,498 United States nuclear weapons workers based on age, smoking history, and occupational exposure to lung carcinogens. Labor unions co-sponsored the program in Department of Energy communities. Participants were eligible for up to 8 annual CT scans over a decade. Group adherence at each annual CT scan was calculated as the percentage who completed the next annual CT scan within 11 to 15 months ("on time"). We measured individual adherence by identifying the percentage of "on time" CT scans completed by each participant. Multivariable logistic regression was used to examine the relation between relevant risk factors and adherence.

We achieved a mean year-to-year adherence of 88.5% among eligible participants for the first through eighth annual CT scan. Mean annual LDCT scan adherence score for all study participants was 68.1%; nearly one-third of participants (30.8%) were 100% adherent. All nodules suspicious for lung cancer received follow-up. 90.4% of 3- and 6-month follow-up scans for indeterminate nodules were completed within 11 months. Advanced age, non-White race, and Midwest or Western U.S. residence were associated with lower adherence.

A high level of adherence is achievable in lung cancer screening implementation programs. Including occupational risk in lung cancer screening more completely addresses risk-related screening eligibility and may increase adherence.