Feasibility of implementing a national lung cancer screening program: Interim results from the Korean Lung Cancer Screening Project (K-LUCAS)

Abstract

Background: Lung cancer screening conducted in high-risk group using low-dose computer tomography (LDCT) has been reported as an effective method to reduce lung cancer mortality in two large randomized-control trials. However, the effectiveness is uncertain when lung cancer screening is expanded to a nationwide population-based program.

Methods: The Korean Lung Cancer Screening Project (K-LUCAS) is a single-arm cohort study that was conducted from February 2017 to evaluate the feasibility of implementing an organized national lung cancer screening program in Korea. High-risk population aged 55-74 years with more than a 30-pack-year smoking history was recruited. Smoking history was obtained from administering questionnaires at national health screening programs or public smoking cessation programs which are already established programs in Korea. The screening results were reported using the Lung Imaging Reporting and Data System (Lung-RADS), suggested by the American College of Radiology. K-LUCAS was performed by a network-based diagnosis supporting system using a computer-aided detection (CAD) program to maintain screening quality. Current smokers were provided with mandatory smoking counseling.

Results: Among 71,829 participants aged 50 years or older in the national health screening program, 5,975 (8.3%) were eligible for lung cancer screening. Among them, 1,062 (17.8%) refused to participate in K-LUCAS. Additionally, 779 participants were recruited in the smoking cessation program. Thus, a total of 5,692 eligible high-risk participants were recruited in this study. Among them, 865 (15.2%) had positive screening results, which requires a further examination; 529 (9.3%) had Lung-RADS category 3 (indeterminate), and 336 (5.9%) had category 4 (suspicious of lung cancer); 42 (0.7%) had confirmed lung cancer. Approximately 66.7% had early-stage lung cancer: 24 (57.1%), stage I and 4 (9.5%), stage II. Six (1.1%) patients developed complications at the time of diagnosis, including one death. The anxiety level related to cancer screening was low. Participation in screening encouraged motivation to quit smoking.

Conclusions: K-LUCAS provided promising evidence supporting the implementation of a national lung cancer screening program to detect early stage lung cancer and promote smoking cessation for participants in Asian population.

Keywords: Lung cancer; low-dose computer tomography (LDCT); screening; smokers.

Figure 1

Categories of evaluating feasibility for implementing a nationwide population-based lung cancer screening program.

Figure 2

Flow of participant recruitment in Korean Lung Cancer Screening Project (K-LUCAS).

Figure 3

Changes in the number (A) and characteristics (B) of participants over time. (A) shows the changes in the number of participants over time. (B) shows the changes in the characteristics of participants over time. “Current smokers” refer to the percentage of currently smoking participants in each month. “Low income” refers to the percentage of low-income group (monthly household income of less than 2 million KRW). “Heavy smokers” refer to the percentage of participants who have a smoking history of 45 pack-years or more. “Less educated” refers to the percentage of participants who finished secondary education or less, and “smoking clinic path” refers to the percentage of participants from participating smoking clinics. The newspaper advertisement targeting the general population was published on September 22, 2017, but it generally takes 1 week for the participant to undergo screening. Here, we compared the participant characteristics before and after October 1, 2017 as we assumed that the effect of the advertisement began around this date.

Figure 4

Lung Imaging Reporting and Data System (Lung-RADS) classification of low-dose computer tomography (LDCT) screening and lung cancer diagnostic follow-up procedure. One participant can undergo more than one diagnostic procedure.