Background: Early detection of lung cancer with low-dose computed tomography (LDCT) screening can shift diagnoses to early-stage disease and improve survival. However, LDCT has several challenges such as high false positive rate and indefinite cost-effectiveness. We report here secondary and exploratory endpoints of the Low-dose CT screening for lung cancer combined with different smoking cessation approach in Finland (LDCT-SC-FI) study including recruitment channels, LDCT performance, and long-term smoking cessation.

Methods: In this study, we randomized 200 current smokers with a significant smoking history in 1:1 fashion to receive a smartphone application or standard of care written materials, both for smoking cessation. All underwent LDCT screening at baseline and at 1-year. Participants were recruited through multiple channels, including newspapers, internet advertisements, and healthcare referrals.

Results: Newspaper advertisements were the most effective recruitment method, accounting for 74.5% of participants while minority came through referrals (2.5%). LDCT screening demonstrated uptake of 96.7% for both rounds combined. Six lung cancers were detected with a positive predictive value of 75%. Of the detected lung cancers, five were at stage I and all of these underwent curative intent treatment. Smoking cessation rates at 1-year were higher in the application (18.3%) than in the control arm (12.8%), though the difference was not statistically significant (odds ratio [OR]: 1.53, 95% confidence interval [CI]: 0.69-3.41).

Interpretation: This study suggests that LDCT screening for lung cancer is feasible in Finland. The screening examination uptake was high with both screening rounds, while the positive predictive value for lung cancer detection remained at good level.