Patterns of cigarette, heated tobacco product, and nicotine vaping product use among Korean adults: Findings from the 2020 ITC Korea Survey.

INTRODUCTION: Non-combustible nicotine products (NCNPs), such as heated tobacco products (HTPs) and nicotine vaping products (NVPs) have gained a significant nicotine market share in South Korea. This descriptive study examined patterns of regular cigarette and NCNP use among South Korean adults. METHODS: Data were from the 2020 International Tobacco Control Korea Survey and included 4016 adults (aged ≥19 years) in the Republic of Korea who were regularly (at least weekly) using at least one NCNP (NVP/HTP, n=2117) and/or smoked cigarettes (n=3763) at the time of the survey. Weighted descriptive estimates were computed to assess respondents' nicotine product use among all respondents (exclusive, dual, or triple use). Thereafter, we identified sociodemographic characteristics associated with NCNP use (n=2117). RESULTS: Among Korean adults who were smoking cigarettes, 83.1% (95% CI: 81.6-84.6) did so exclusively, and 16.9% (95% CI: 15.4-18.4) smoked cigarettes and used NCNPs. Among those who used HTPs (n=1877), 14.9% (95% CI: 11.5-18.4) did so exclusively, 59.6% used HTPs and smoked cigarettes (95% CI: 55.4-63.1), 4.2% used HTPs and vaped (95% CI: 11.5-18.4), and 21.6% (95% CI: 18.9-24.2) used all three products. Of adults who used HTPs and smoked cigarettes, 86.6% smoked daily. Among those who vaped (n=865), 13.3% did so exclusively (95% CI: 9.4-17.1), 55.6% (95% CI: 49.6-61.5) vaped and smoked cigarettes, 5.1% (95% CI: 1.7-8.6) used HTPs and vaped, and 26.1% (95% CI: 22.1-30.1) used all three products. Of adults who vaped and smoked cigarettes, 82.4% (95% CI: 77.1-87.7) smoked daily. CONCLUSIONS: Cigarettes remain the most commonly used nicotine product in South Korea, and among adults using heated tobacco and/or vaping products, the majority were also smoking. Research is urgently needed to assess whether adults who are using an NCNP are doing so to quit, or rather to complement their cigarette smoking.

The clinical effect of an electric massage chair on chemotherapy-induced nausea and vomiting in cancer patients: randomized phase II cross-over trial.

PURPOSE: Chemotherapy-induced nausea and vomiting (CINV) is a common adverse events in cancer patients and can negatively affect their quality of life (QoL). This study aimed to evaluate the clinical efficacy of an electric massage chair (EMC) for the treatment of CINV. METHODS: A randomized phase II cross-over trial was conducted on solid cancer patients who received moderate (MEC) to high emetogenic chemotherapy (HEC). The participants were randomly assigned to receive their first chemotherapy either on a standard bed (Group A) or in an EMC (Group B) during the infusion. The patients were then crossed over to the next cycle. CINV and QoL questionnaires were collected from the participants. RESULTS: A total of 59 patients completed the trial protocol and were included in the analysis, with 29 and 30 patients in Groups A and B, respectively. The mean INVR (Index of Nausea, Vomiting, and Retching) score in the 2nd day of the first cycle was higher in Group B (3.63 ± 5.35) than Group A (2.76 ± 4.78), but the difference was not statistically significant (p = 0.5367). The complete response rate showed little difference between the groups. Among the high-emetic risk subgroups, patients who received HEC (p = 0.04595), younger patients (p = 0.0108), and non-colorectal cancer patients (p = 0.0495) presented significantly lower CINV scores when EMC was applied. CONCLUSION: Overall, there was no significant difference in INVR scores between standard care and EMC. Applying EMC at the first chemotherapy infusion may help preserve QoL and reduce CINV in high-risk patients. TRIAL REGISTRATION: KCT0008200, 17/02/2023, Retrospectively registered.

Strategies to Improve Smoking Cessation for Participants in Lung Cancer Screening Program: Analysis of Factors Associated with Smoking Cessation in Korean Lung Cancer Screening Project (K-LUCAS).

PURPOSE: Smoking cessation intervention is one of the key components of successful lung cancer screening program. We investigated the effectiveness and related factors of smoking cessation services provided to the participants in a population-based lung cancer screening trial. MATERIALS AND METHODS: The Korean Lung Cancer Screening Project (K-LUCAS) is a nationwide, multi-center lung cancer screening trial that evaluates the feasibility of implementing population-based lung cancer screening. All 5,144 current smokers who participated in the K-LUCAS received a mandatory smoking cessation counseling. Changes in smoking status were followed up using a telephone survey in 6 months after lung cancer screening participation. The lung cancer screening's impact on smoking cessation is analyzed by variations in the smoking cessation interventions provided in screening units. RESULTS: Among 4,136 survey responders, participant's motivation to quit smoking increased by 9.4% on average after lung cancer screening. After 6 months from the initial screening, 24.3% of participants stopped smoking, and 10.6% of participants had not smoked continuously for at least 6 months after screening. Over 80% of quitters stated that participation in lung cancer screening motivated them to quit smoking. Low-cost public smoking cessation program combined with lung cancer screening increased the abstinence rates. The smokers were three times more likely to quit smoking when the smoking cessation counseling was provided simultaneously with low-dose computed tomography screening results than when provided separately. CONCLUSION: A mandatory smoking cessation intervention integrated with screening result counselling by a physician after participation in lung cancer screening could be effective for increasing smoking cessation attempts.

Perceptions of harmfulness of heated tobacco and nicotine vaping products compared to cigarettes, and the association of advertising exposure on harm perceptions among adults who smoke in South Korea: Cross-sectional findings from the 2020 ITC Korea Survey.

INTRODUCTION: Heated tobacco products (HTPs) and nicotine vaping products (NVPs) both are legal consumer products in the Republic of Korea. Little is known about perceptions of harmfulness of HTPs and NVPs relative to cigarettes in South Korea among adults who smoke, and how exposure to marketing may be associated with harmfulness perceptions. METHODS: This study used data from the 2020 International Tobacco Control (ITC) Korea Survey, and included 3713 adult (aged 19 years) cigarette smokers who were: 1) exclusive smokers (n=1845); 2) dual HTP + cigarette consumers (n=1130); 3) dual NVP + cigarette consumers (n=224); and 4) triple consumers (all three products, n=514). Weighted multinomial regression models were conducted to estimate smokers' perceptions of harmfulness of HTPs and NVPs compared to cigarettes, NVPs to HTPs, and self-reported exposure to HTP/NVP advertising. Analyses compared the perceptions of harmfulness between the four different consumer groups, and tested whether exposure to HTP/NVP advertising was associated with perceptions of lower relative harm. RESULTS: Among all respondents, 27.5% believe that HTPs are less harmful than cigarettes and 23.4% believe that NVPs are less harmful than cigarettes. Exclusive cigarettes smokers were significantly less likely to perceive that HTPs and NVPs are less harmful than cigarettes compared to dual HTP + cigarette consumers, dual NVP + cigarette consumers, and triple consumers (all p<0.001). Half of respondents perceive NVPs as equally harmful as HTPs (14.1% perceive NVPs as more harmful than HTPs). Exposure to HTP/NVP advertising was associated with perceiving these products as less harmful than cigarettes. CONCLUSIONS: About one-quarter of Korean cigarette smokers perceive HTPs and NVPs as less harmful than cigarettes. Further investigation is required to understand how harm perceptions and HTP/NVP advertising are related to changes in product use, such as switching between products, using multiple products, or discontinuing all product use.

Reasons for Initiation and Regular Use of Heated Tobacco Products among Current and Former Smokers in South Korea: Findings from the 2020 ITC Korea Survey.

South Korea is the world's second-largest heated tobacco product (HTP) market after Japan. HTP sales in South Korea have increased rapidly since May 2017, accounting for 10.6% of the total tobacco market in 2020. Despite this, little is known as to why HTP consumers who were current and former smokers started using HTPs and used them regularly. We analyzed cross-sectional data for 1815 adults (aged 19+) who participated in the 2020 International Tobacco Control (ITC) Korea Survey, of whom 1650 were HTP-cigarette consumers (those who reported smoking cigarettes and using HTPs ≥ weekly) and 165 were exclusive HTP consumers (using HTPs ≥ weekly) who were former or occasional smokers (smoking cigarette < weekly). Respondents were asked to report the reason(s) they used HTPs, with 25 possible reasons for HTP-cigarette consumers and 22 for exclusive HTP consumers. The most common reasons for initiating HTP use among all HTP consumers were out of curiosity (58.9%), family and friends use HTPs (45.5%), and they like the HTP technology (35.9%). The most common reasons for regularly using HTPs among all HTP consumers were that they were less smelly than cigarettes (71.3%), HTPs are less harmful to own health than cigarettes (48.6%), and stress reduction (47.4%). Overall, 35.4% of HTP-cigarette consumers reported using HTPs to quit smoking, 14.7% to reduce smoking but not to quit, and 49.7% for other reasons besides quitting or reducing smoking. In conclusion, several common reasons for initiating and regularly using HTPs were endorsed by all HTP consumers who were smoking, had quit smoking completely, or occasionally smoked. Notably, only about one-third of HTP-cigarette consumers said they were using HTPs to quit smoking, suggesting that most had no intention of using HTPs as an aid to quit smoking in South Korea.

Factors Associated with Quit Intentions among Adult Smokers in South Korea: Findings from the 2020 ITC Korea Survey.

Background: South Korea has made substantial progress on tobacco control, but cigarette smoking prevalence is still high. Previous studies were conducted before the use of nicotine vaping products (NVPs) or heated tobacco products (HTPs) became popular. Thus, whether the concurrent use of NVPs or HTPs affects quit intentions among Korean smokers remains a question that needs to be explored. This study aims to identify predictors of quit intentions among cigarette-only smokers and concurrent users of cigarettes and NVPs or HTPs. Methods: Data were from the 2020 International Tobacco Control Korea Survey. Included in the analysis were 3778 adult cigarette smokers: 1900 at-least-weekly exclusive smokers and 1878 at-least-weekly concurrent smokers and HTP or NVP users. Bivariate and multivariable logistic regression analyses were conducted. Results: Quit intentions were reported by 66.4% of respondents. Factors significantly associated with quit intentions included younger age, having a spouse/partner, lower nicotine dependence, reporting a past quit attempt, regretting starting smoking, believing that smoking had damaged health, worrying that smoking will damage future health, and perceiving health benefits of quitting. Current use of NVPs or HTPs was not significantly associated with quit intentions. Conclusions: This study contributes the following to current literature: intrinsic health-related beliefs were more important than societal norms in shaping quit intentions. These findings should be considered in shaping future smoking cessation policies, such as reinforcing education programs that emphasize the benefits of quitting for personal health reasons, lowering nicotine dependence, and encouraging multiple quit attempts and successful quitting.

Impact of COVID-19 on cancer screening in South Korea.

The coronavirus disease (COVID-19) pandemic significantly declined cancer screening rates worldwide. Its impact on the South Korean population is unclear, depending on socioeconomic status (SES), residence, and history of chronic disease. This study utilized data (2018-2020) from the Korean National Cancer Screening Survey, an annual cross-sectional study employing nationally representative random sampling. Cancer screening rates were defined as the proportion of the eligible population who received respective cancer screening within the last 1 year and investigated four major cancers (stomach, colorectal, breast, and cervical). Screening rates every year were compared with screening rate ratios (SRRs) and the corresponding 95% confidence intervals (CIs). Between 2019 and 2020, screening rates declined significantly by 23%, 17%, 12%, and 8% for colorectal cancer (SRR 0.77; 95% CI 0.73-0.82), stomach cancer (SRR 0.83; 95% CI 0.79-0.87), breast cancer (SRR 0.88; 95% CI 0.82-0.93), and cervical cancer (SRR 0.92; 95% CI 0.87-0.97), respectively. Regardless of cancer type, screening was significantly lower in metropolitan residents, those with higher SES, and, interestingly, those without a history of chronic diseases. The significant decline in cancer screening during the pandemic requires urgent political intervention to reduce the burden of future cancer incidence and mortality.

Online information analysis on pancreatic cancer in Korea using structural topic model.

Inappropriate information on a deadly and rare disease can make people vulnerable to problematic decisions, leading to irreversible bad outcomes. This study explored online information exchanges on pancreatic cancer. We collected 35,596 questions and 83,888 answers related to pancreatic cancer from January 1, 2003 to May 31, 2020, from Naver, the most popular Korean web portal. We also collected 8495 news articles related to pancreatic cancer during the same period. The study methods employed were structural topic modeling, keyword frequency analysis, and qualitative coding of medical professionals. The number of questions and news articles increased over time. In Naver's questions, topics on symptoms and diagnostic tests regarding pancreatic cancer increased in proportion. The news topics on new technologies related to pancreatic cancer from various companies increased as well. The use of words related to back pain-which is not an important early symptom in pancreatic cancer-and biomarker tests using blood increased over time in Naver's questions. Based on 100 question samples related to symptoms and diagnostic tests and an analysis of the threaded answers' appropriateness, there was considerable misinformation and commercialized information in both categories.

Methods of the 2020 (Wave 1) International Tobacco Control (ITC) Korea Survey.

This article presents methods used in the 2020 International TC Korea Wave 1 (KRA1) Survey. To date, three cohorts of Korean respondents have participated in the larger ITC Korea Project (cohort 1: 2005-2014, cohort 2: 2016, and cohort 3: 2020-present). The overall objectives of the ITC KRA1 Survey were to examine the use of cigarettes, heated tobacco products (HTPs), e-cigarettes (ECs); whether HTPs might help smokers quit; and the effectiveness of tobacco control policies, such as large graphic warnings, high cigarette taxes, and smoking bans in public places. The KRA1 Survey measures were identical or functionally similar to those of the ITC Japan Survey and, to a lesser extent, those of other ITC countries. Key measures assessed sociodemographic characteristics of respondents; the use of combustible cigarettes, e-cigarettes, and heated tobacco products; and measures assessing policies of the WHO Framework Convention on Tobacco Control, including price and tax (Article 6), smoke-free laws (Article 8), health warnings (Article 11), education, communication and public awareness (Article 12), advertising, promotion, and sponsorship restrictions (Article 13), and support for cessation (Article 14). Adult tobacco and/or nicotine users aged ≥19 years in South Korea were recruited by a commercial survey firm from its online panel. Overall, 4794 respondents completed the KRA1 Survey. The cooperation rate was 97.4% and the response rate was 15.2%. The cohort design permits assessment of transitions in products used among users in South Korea and evaluations of the impact of policies on tobacco and/or nicotine products used and transitions in use.

Cost Utility Analysis of a Pilot Study for the Korean Lung Cancer Screening Project.

PURPOSE: The aim of this study was to evaluate the cost utility of a pilot study of Korean Lung Cancer Screening Project. MATERIALS AND METHODS: We constructed a Markov model consisting of 26 states based on the natural history of lung cancer according to the Surveillance, Epidemiology, and End Results summary stage (localized, regional, distant). In the base case, people aged 55-74 years were under consideration for annual screening. Costs and quality-adjusted life years were simulated to calculate the incremental cost utility ratio. Sensitivity analyses were performed on the uncertainty associated with screening target ages, stage distribution, cost, utility, mortality, screening duration, and discount rate. RESULTS: The base case (US$25,383 per quality-adjusted life year gained) was cost-effective compared to the scenario of no screening and acceptable considering a willingness-to-pay threshold of US$27,000 per quality-adjusted life years gained. In terms of the target age of screening, the age between 60 and 74 years was the most cost-effective. Lung cancer screening was still cost-effective in the sensitivity analyses on the cost for treatment, utility, mortality, screening duration, and less than 5% discount rates, although the result was sensitive to a rise in positive rates or variation of stage distribution. CONCLUSION: Our results showed the cost-effectiveness of annual low-dose computed tomography screening for lung cancer in high-risk populations.

Effectiveness of National Residential Smoking Cessation Program.

We aimed to investigate the effectiveness of the Korean national five-day residential smoking cessation program and the factors affecting the long-term smoking cessation of participants. The residential smoking cessation program (2017-2018) recruited smokers with a smoking duration ≥ 20 years and who have attempted to quit smoking more than twice and/or smokers with chronic morbidities. Participants underwent an intensive intervention, including individual psychological therapy, group therapy, medical counseling, and pharmacotherapy. The 6-month continuous abstinence rate (CAR) was assessed via self-reports, the urine cotinine levels, and/or expired-air carbon monoxide levels. Logistic regression was used to analyze the adjusted odds ratio (aOR) to assess factors related to smoking cessation. Overall, 484 participants who completed the residential program and questionnaire were evaluated. The 3- and 6-month CAR were 81.82% and 63.22%, respectively. The aOR of 6-month continuous abstinence was lower among participants with severe nicotine dependence (aOR: 0.46, 95% confidence interval [CI]: 0.26-0.81) and higher among participants with combination therapy of varenicline with short-term nicotine replacement therapy (NRT) (aOR: 1.64, 95% CI: 1.07-2.51), with higher self-efficacy (aOR: 1.97, 95% CI: 1.15-3.37). The residential smoking cessation program was effective. High self-efficacy, combination therapy of varenicline with short-term NRT, and low nicotine dependence were associated with a high 6-month CAR.

Preparedness for containing COVID-19 outbreak in mass religious gathering with non-pharmaceutical interventions (NPIs).

BACKGROUND: The COVID-19 outbreaks associated with mass religious gatherings which have the potential of invoking epidemics at large scale have been a great concern. This study aimed to evaluate the risk of outbreak in mass religious gathering and further to assess the preparedness of non-pharmaceutical interventions (NPIs) for preventing COVID-19 outbreak in this context. METHODS: The risk of COVID-19 outbreak in mass religious gathering was evaluated by using secondary COVID-19 cases and reproductive numbers. The preparedness of a series of NPIs for preventing COVID-19 outbreak in mass religious gathering was then assessed by using a density-dependent model. This approach was first illustrated by the Mazu Pilgrimage in Taiwan and validated by using the COVID-19 outbreak in the Shincheonji Church of Jesus (SCJ) religious gathering in South Korea. RESULTS: Through the strict implementation of 80% NPIs in the Mazu Pilgrimage, the number of secondary cases can be substantially reduced from 1508 (95% CI: 900-2176) to 294 (95% CI: 169-420) with the reproductive number (R) significantly below one (0.54, 95% CI: 0.31-0.78), indicating an effective containment of outbreak. The expected number of secondary COVID-19 cases in the SCJ gathering was estimated as 232 (basic reproductive number (R0) = 6.02) and 579 (R0 = 2.50) for the first and second outbreak, respectively, with a total expected cases (833) close to the observed data on high infection of COVID-19 cases (887, R0 = 3.00). CONCLUSION: We provided the evidence on the preparedness of NPIs for preventing COVID-19 outbreak in the context of mass religious gathering by using a density-dependent model.

Decreasing trends in thyroid cancer incidence in South Korea: What happened in South Korea?

BACKGROUND: South Korea has the highest incidence of thyroid cancer in the world. Our study examined the trends in thyroid cancer incidence by the histologic type, cancer stage, and age group and explored possible factors that affected thyroid cancer trends. METHODS: We conducted a descriptive epidemiological study using the national cancer registry data and cause of death data from 1999 to 2016 in South Korea. Age-standardized rates were calculated using Segi's world standard population. Joinpoint regression analysis was applied to determine the changing point of thyroid cancer trends according to histologic type; Surveillance, Epidemiology, and End Results (SEER) summary stage; and age groups by sex. RESULTS: The age-standardized incidence of thyroid cancer in both men and women increased from 6.3 per 100,000 people in 1999 to 63.4 per 100,000 in 2012 but declined from 2012 to 2016, before the debates for over diagnosis of thyroid cancer began in 2014. The age-standardized mortality rate of thyroid cancer, incidence of distant thyroid cancer, and incidence of regional and localized thyroid cancer started to decline since early 2000, 2010, and 2012, respectively. In addition, thyroid cancer prevalence in thyroid nodules showed decreasing trends from 1999-2000 to 2013-2014. CONCLUSIONS: The incidence of thyroid cancer began declining from 2012, before the debates for over diagnosis of thyroid cancer began in 2014. Changes in guidelines for thyroid nodule examinations may have affected this inflection point. Moreover, the debates for over diagnosis of thyroid cancer may have accelerated the decline in thyroid cancer.

Public opinion on implementing the National Lung Cancer Screening Program in Korea.

BACKGROUND: Lung cancer screening for high-risk population using low-dose computed tomography is a valid strategy to reduce lung cancer mortality. This study investigated public opinions toward the initiation and participation in the National Lung Cancer Screening Program (NLCSP) launched in Korea. METHODS: In this cross-sectional analysis of the 2018 Korean National Cancer Screening Survey, we analyzed the responses related to lung cancer screening. Eligible participants for NLCSP are aged 55‒74 years with at least 30 pack-years of smoking history. We compared public opinions on implementing lung cancer screening according to smoking status and eligibility for NLCSP. RESULTS: Among 3,495 respondents, 205 (5.9%) were eligible for screening. Most of the respondents (71.2%) agreed with implementing NLCSP. Agreement rates were relatively lower in never smokers (66.2%) and higher in former (80.8%) and current smokers (82.3%). Factors associated with agreement included the presence of private health insurance [odds ratio (OR) 1.36, 95% confidence interval (CI), 1.04-1.78], regular health checkup (OR 2.10, 95% CI, 1.72-2.57), and smoking history (former, OR 1.66, 95% CI, 1.09-2.55; current, OR 1.97, 95% CI, 1.45-2.67). Preference of the screening facilities showed that quality was considered more important than accessibility (46.9% vs. 31.9%). Furthermore, people were more affirmative (75.5%) towards receiving mandatory smoking cessation counseling included in NLCSP. CONCLUSIONS: Public agreement and active participation of the eligible population are key factors in the successful implementation of NLCSP. Our data would be a valuable resource in building appropriate strategies to maximize the benefits of nationwide lung cancer screening.

Effectiveness of radiologist training in improving reader agreement for Lung-RADS 4X categorization.

OBJECTIVES: To identify the agreement on Lung CT Screening Reporting and Data System 4X categorization between radiologists and an expert-adjudicated reference standard and to investigate whether training led to improvement of the agreement measures and diagnostic potential for lung cancer. METHODS: Category 4 nodules in the Korean Lung Cancer Screening Project were identified retrospectively, and each 4X nodule was matched with one 4A or 4B nodule. An expert panel re-evaluated the categories and determined the reference standard. Nineteen radiologists were asked to determine the presence of CT features of malignancy and 4X categorization for each nodule. A review was performed in two sessions, and training material was given after session 1. Agreement on 4X categorization between radiologists and the expert-adjudicated reference standard and agreement between radiologist-assessed 4X categorization and lung cancer diagnosis were evaluated. RESULTS: The 48 expert-adjudicated 4X nodules and 64 non-4X nodules were evenly distributed in each session. The proportion of category 4X decreased after training (56.4% ± 16.9% vs. 33.4% ± 8.0%; p < 0.001). Cohen's κ indicated poor agreement (0.39 ± 0.16) in session 1, but agreement improved in session 2 (0.47 ± 0.09; p = 0.03). The increase in agreement in session 2 was observed among inexperienced radiologists (p < 0.05), and experienced and inexperienced reviewers exhibited comparable agreement performance in session 2 (p > 0.05). All agreement measures between radiologist-assessed 4X categorization and lung cancer diagnosis increased in session 2 (p < 0.05). CONCLUSION: Radiologist training can improve reader agreement on 4X categorization, leading to enhanced diagnostic performance for lung cancer. KEY POINTS: • Agreement on 4X categorization between radiologists and an expert-adjudicated reference standard was initially poor, but improved significantly after training. • The mean proportion of 4X categorization by 19 radiologists decreased from 56.4% ± 16.9% in session 1 to 33.4% ± 8.0% in session 2. • All agreement measures between the 4X categorization and lung cancer diagnosis increased significantly in session 2, implying that appropriate training and guidance increased the diagnostic potential of category 4X.

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

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.

Guidelines for Cancer Care during the COVID-19 Pandemic in South Korea.

At the end of 2019, the cause of pneumonia outbreaks in Wuhan, China, was identified as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In February 2020, the World Health Organization named the disease cause by SARS-CoV-2 as coronavirus disease 2019 (COVID-19). In response to the pandemic, the Korean Cancer Association formed the COVID-19 task force to develop practice guidelines. This special article introduces the clinical practice guidelines for cancer patients which will help oncologists best manage cancer patients during the COVID-19 pandemic.

Optimum diameter threshold for lung nodules at baseline lung cancer screening with low-dose chest CT: exploration of results from the Korean Lung Cancer Screening Project.

OBJECTIVES: To explore the optimum diameter threshold for solid nodules to define positive results at baseline screening low-dose CT (LDCT) and to compare two-dimensional and volumetric measurement of lung nodules for the diagnosis of lung cancers. METHODS: We included consecutive participants from the Korean Lung Cancer Screening project between 2017 and 2018. The average transverse diameter and effective diameter (diameter of a sphere with the same volume) of lung nodules were measured by semi-automated segmentation. Diagnostic performances for lung cancers diagnosed within 1 year after LDCT were evaluated using area under receiver-operating characteristic curves (AUCs), sensitivities, and specificities, with diameter thresholds for solid nodules ranging from 6 to 10 mm. The reduction of unnecessary follow-up LDCTs and the diagnostic delay of lung cancers were estimated for each threshold. RESULTS: Fifty-two lung cancers were diagnosed among 10,424 (10,141 men; median age 62 years) participants within 1 year after LDCT. Average transverse (0.980) and effective diameters (0.981) showed similar AUCs (p = .739). Elevating the average transverse diameter threshold from 6 to 9 mm resulted in a significantly increased specificity (91.7 to 96.7%, p < .001), a modest reduction in sensitivity (96.2 to 94.2%, p = .317), a 60.2% estimated reduction of unnecessary follow-up LDCTs, and a diagnostic delay in 1.9% of lung cancers. Elevating the threshold to 10 mm led to a significant reduction in sensitivity (86.5%, p = .025). CONCLUSIONS: Elevating the diameter threshold for solid nodules from 6 to 9 mm may lead to a substantial reduction in unnecessary follow-up LDCTs with a small proportion of diagnostic delay of lung cancers. KEY POINTS: • Elevation of the diameter threshold for solid nodules from 6 to 9 mm can substantially reduce unnecessary follow-up LDCTs with a small proportion of diagnostic delay of lung cancers. • The average transverse and effective diameters of lung nodules showed similar performances for the prediction of a lung cancer diagnosis.

Risk-based prediction model for selecting eligible population for lung cancer screening among ever smokers in Korea.

BACKGROUND: This study developed a new lung cancer risk prediction model for the Korean population and evaluated the performance, compared to the previously reported risk models developed in Western countries. METHODS: Among the 6,811,893 people who received health examinations from the Korean National Health Insurance Service, 969,351 ever-smokers (40-79 years) were included. Performance of Bach, Lung Cancer Risk Models for Screening, PLCOM2012, Pittsburgh, and Liverpool Lung Project models were evaluated. The ever-smokers were divided into the training and validation datasets by random sampling. The lung cancer risk model was developed and validated in the Korean population. The efficiency of model-based selection for lung cancer screening was compared with the eligible criteria of the National Lung Screening Trial (NLST). RESULTS: The Korean lung cancer risk model showed the area under the curve and expected/observed (E/O) ratio of 0.816 and 0.983 in the training dataset and 0.816 and 0.988 in the validation dataset. The Korean lung cancer risk model included age-mean of age, square of age-mean of age, sex, square root of pack-years of smoking, years since cessation, physical activity, alcohol consumption, body mass index, and medical history of chronic pulmonary obstructive disease, emphysema, pneumoconiosis, and interstitial pulmonary disease. Compared with the NLST criteria, the Korean lung cancer risk model's cut-off criteria (>2.1%) had more improved sensitivity (61.4% vs. 44.3%) and positive predictive value (4.1% vs. 2.9%). The Korean lung cancer risk model showed better discrimination and calibration than previously developed models in Western population. CONCLUSIONS: The Korean lung cancer risk model can select eligible population for low-dose computed tomography screening among the Asian population. The efficiency of risk model-based selection for lung cancer screening is superior to that of fixed criteria-based selection.