Survival of Lung Cancer Patients Considering Criteria for Lung Cancer Screening: Analysis of the Korean Lung Cancer Registry, 2014-2016

Background: This study compared survival between lung cancer patients meeting criteria for the National Lung Cancer Screening Program in Korea launched in 2019 and expanded US Preventive Service Task Force (USPSTF) recommendations. Methods: We assessed all-cause mortality based on the Korean Lung Cancer Registry (KLCR), including lung cancer patients diagnosed in 2014–2016. We compared survival among lung cancer patients eligible for extended USPSTF criteria (age 50–80 years and ≥20 pack-years) and those meeting current criteria (age 54–74 years and ≥30 pack-years, current or within the past 15 years). The nearest neighbor propensity-score matching was performed to generate a matched set. Kaplan–Meier curves were generated to compare survival among groups; differences in survival were analyzed using the stratified log-rank test. The mortality risk was estimated based on a Cox proportional hazards regression model and the robust standard error was calculated. Results: Of 8110 patients, 40·4% and 25·4% met the extended USPSTF eligibility criteria and National Lung Cancer Screening Program (NLCSP) criteria, respectively. Overall mortality risk was not significantly different between the extended younger age group and the NLCSP group (hazard ratio [HR] [95% confidence interval (CI)]: 0·96 [0·72–1·28]). The extended older age group had a significantly higher mortality risk (HR [95% CI]: 1·38 [1·24–1·54]). Mortality risk was not significantly different between patients who smoked 20–29 pack-years and those who smoked ≥30 pack-years (HR [95% CI]: 0·90 [0·79–1·02]). Conclusion: Lung cancer patients aged 50–53 years and those with a 20–29 pack-years smoking history exhibited similar mortality risk to individuals meeting current criteria, while patients aged 75–80 years were at a higher risk of death. Although we verified similar or higher mortality risks in extended subgroups, a careful assessment of the benefits and harms of the screening tests is necessary when contemplating the extension of criteria.