Lung Cancer Screening Guidelines Research Articles

Perceptions and Interest in Lung Cancer Screening by Smoking Status: A Cross-Sectional Study of HINTS 6 (2022).

Lung cancer screening guidelines prioritize individuals with a history of smoking due to their higher risk of the disease. Our study examines the awareness and interest in low-dose computed tomography (LDCT) lung cancer screening among different smoking statuses using data from the National Cancer Institute's Health Information National Trends Survey (HINTS) 6 (2022). We analyzed data from HINTS 6, including 3915 participants on smoking status, LDCT screening, and telehealth use. Participants were categorized as current smokers, former smokers, and non-smokers. Current smokers had the highest likelihood of being recommended for LDCT screening (OR: 7.1, aOR: 10.4) compared with non-smokers. Former smokers also had increased odds of screening recommendations (OR: 3.1, aOR: 3.4) than non-smokers. Despite higher screening recommendations, current smokers exhibited significantly lower interest in cancer screening (interest rating score: 2.1) compared with non-smokers (interest rating score: 2.4) and former smokers (interest rating score: 2.5). Current smokers rated their telehealth care experiences more positively in terms of care quality compared with non-smokers. Our findings underscore a gap in cancer screening interest among current smokers despite their higher likelihood of being recommended for LDCT screening. The favorable perception of telehealth among current smokers provides an opportunity to enhance engagement and promote LDCT scan through telehealth care.

Family Physician Education and Barriers to Promoting Smoking Cessation: A Multiservice Investigation.

Cigarette smoking remains the leading cause of preventable disease and death in the United States. Brief discussions with doctors increase cessation rates by two-thirds, and physicians trained in smoking cessation are more likely to perform counseling. Multiple organizations also recommend connecting counseling with lung cancer screening (LCS), yet physicians and patients report a lack of such integration. We sought to characterize the education received and the barriers to providing smoking cessation counseling, and to determine its integration with LCS among military Family Medicine physicians. This is a cross-sectional study of registered attendees of 2022 Uniformed Services Academy of Family Physicians Annual Conference. Our study aimed to: (1) Assess the amount of formal smoking cessation education during and after residency; (2) assess barriers to providing smoking cessation within the military health care system; and (3) assess if physicians connect smoking cessation counseling and LCS. Descriptive statistics with chi-squared analysis were used to analyze the survey results. With a response rate of 61% (n = 323/487), most participants reported receiving <3 sessions of formal education during residency (72.9%) and <3 h after residency (76.2%). Forty-eight percent cited their health care system never or rarely provided resources on smoking cessation. Time was the largest barrier to promoting smoking cessation (62.6%) and to integrating it with LCS (56.7%), although a considerable percentage also cited lack of supporting staff (34.3%). Furthermore, only 50.6% of respondents always reported counseling on smoking cessation with LCS. Smoking cessation education is provided in family medicine residencies but rarely offered afterwards. Time and lack of support staff and resources are recognized as notable barriers within the military health care system. A large proportion of uniformed Family Medicine physicians also do not link LCS guidelines with patient education on tobacco cessation and resources. Further research is needed to guide interventions to overcome these challenges within the military health care system.

Development of Lung Cancer Risk Prediction Machine Learning Models for Equitable Learning Health System: Retrospective Study.

A significant proportion of young at-risk patients and nonsmokers are excluded by the current guidelines for lung cancer (LC) screening, resulting in low-screening adoption. The vision of the US National Academy of Medicine to transform health systems into learning health systems (LHS) holds promise for bringing necessary structural changes to health care, thereby addressing the exclusivity and adoption issues of LC screening. This study aims to realize the LHS vision by designing an equitable, machine learning (ML)-enabled LHS unit for LC screening. It focuses on developing an inclusive and practical LC risk prediction model, suitable for initializing the ML-enabled LHS (ML-LHS) unit. This model aims to empower primary physicians in a clinical research network, linking central hospitals and rural clinics, to routinely deliver risk-based screening for enhancing LC early detection in broader populations. We created a standardized data set of health factors from 1397 patients with LC and 1448 control patients, all aged 30 years and older, including both smokers and nonsmokers, from a hospital's electronic medical record system. Initially, a data-centric ML approach was used to create inclusive ML models for risk prediction from all available health factors. Subsequently, a quantitative distribution of LC health factors was used in feature engineering to refine the models into a more practical model with fewer variables. The initial inclusive 250-variable XGBoost model for LC risk prediction achieved performance metrics of 0.86 recall, 0.90 precision, and 0.89 accuracy. Post feature refinement, a practical 29-variable XGBoost model was developed, displaying performance metrics of 0.80 recall, 0.82 precision, and 0.82 accuracy. This model met the criteria for initializing the ML-LHS unit for risk-based, inclusive LC screening within clinical research networks. This study designed an innovative ML-LHS unit for a clinical research network, aiming to sustainably provide inclusive LC screening to all at-risk populations. It developed an inclusive and practical XGBoost model from hospital electronic medical record data, capable of initializing such an ML-LHS unit for community and rural clinics. The anticipated deployment of this ML-LHS unit is expected to significantly improve LC-screening rates and early detection among broader populations, including those typically overlooked by existing screening guidelines.

Examination of Firefighting as an Occupational Exposure Criteria for Lung Cancer Screening.

Firefighting is known to be carcinogenic to humans. However, current lung cancer screening guidelines do not account for occupational exposure. We hypothesize that firefighting is an independent risk factor associated with the development of high-risk lung nodules on low-dose CT (LDCT). Members of a firefighter's union underwent LDCT at a single institution between April 2022 and June 2023 within a lung cancer screening program. Results were interpreted by designated chest radiologists and reported using the Lung-RADS scoring system. Demographic and radiographic data were recorded, and summary statistics are reported. 1347 individuals underwent lung cancer screening, with a median age of 51years (IQR 42-58), including 56 (4.2%) females. Overall, 899 (66.7%) were never smokers, 345 (25.6%) were former smokers, and 103 (7.7%) were current smokers. There were 41 firefighters (3.0%) who had high-risk (Lung-RADS 3 or 4) nodules requiring intervention or surveillance, of which 21 (1.5%) were Lung-RADS 3 and 20 (1.5%) that were Lung-RADS 4. Of the firefighters with high-risk nodules, only 6 (14.6%) were eligible for LDCT based on current screening guidelines. There were 7 high-risk nodules (0.5%) that required procedural intervention, 6 (85.7%) of which were from the non-screening eligible cohort. There were also 20 never-smoking firefighters (57.1%) with high-risk nodules that were non-screening eligible. Firefighting, even in the absence of smoking history, may be associated with the development of high-risk lung nodules on LDCT. Carefully selected occupational exposures should be considered in the development of future lung cancer screening guidelines.

Qualitative interviews for hospitalists addressing lung cancer screening

Novel strategies are needed to improve low rates of lung cancer screening (LCS) in the US. Seeking to determine hospitalists’ perspectives on leveraging hospitalizations to identify patients eligible for LCS, we performed qualitative interviews with eight hospitalists from two hospitals within a large integrated healthcare system. The interviews used semi-structured questions to assess (1) knowledge and practice of general screening and LCS guidelines from the United States Preventive Services Task Force (USPSTF), (2) identification of smoking history, and (3) hospitalists’ views on how data obtained during hospitalization may be utilized to improve general screening and LCS post hospitalization. We ultimately reached the conclusion that hospitalists would support a dedicated program to identify hospitalized patients eligible for LCS and facilitate testing after discharge. Efforts to identify patients and arrange subsequent screening should be performed by team members outside the inpatient team.

Early-Stage Lung Cancer in the Era of Lung Cancer Screening: Veterans Health Administration Outperforms Other Insurance Models

BackgroundLung cancer screening guidelines were introduced in the United States in 2013, with variable implementation. This study evaluated temporal diagnostic trends in non-small cell lung cancer (NSCLC) diagnosis since the introduction of these guidelines. MethodsThis retrospective cohort analysis used data from the Veterans Administration Corporate Data Warehouse and the National Cancer Database. We evaluated temporal trends in the distribution of NSCLC stage at the time of diagnosis along with differences based on insurance coverage type, including uninsured, privately insured, Medicare, Medicaid, and Veterans Affairs (VA) coverage, with adjustment for clinically relevant variables. ResultsAmong 1,450,965 patients diagnosed from 2006 to 2020, the proportion of NSCLC cases diagnosed at stage I increased in all insurance groups by 12.74%, 2%, 0.25%, and 2.57% for the VA, Medicare, private insurance, and Medicaid, respectively. If all insurance systems achieved the unadjusted stage distribution seen in the Veterans Health Administration, an additional 45,684 patients would be diagnosed with stage I NSCLC and 65,933 fewer patients would be diagnosed with stage IV disease. ConclusionsFor patients with any form of insurance, there has been an increase in the proportion of early-stage NSCLC (stage I and II) and a corresponding decrease in the proportion of stage III and IV since the introduction of national lung cancer screening guidelines. As the largest integrated single-payer health care system in the United States, the VA dramatically outperforms other insurance types, perhaps attributable to universal coverage and robust lung cancer screening programs.

Characterizing the accuracy of robotic bronchoscopy in localization & targeting of small pulmonary lesions.

Considering the recent implementation of lung cancer screening guidelines, it is crucial that small pulmonary nodules are accurately diagnosed. There is a significant need for quick, precise, and minimally invasive biopsy methods, especially for patients with small lung lesions in the outer periphery. Robotic bronchoscopy (RB) has recently emerged as a novel solution. The purpose of this study was to evaluate the accuracy of RB compared to the existing standard, electromagnetic navigational bronchoscopy (EM-NB). A prospective, single-blinded, and randomized-controlled study was performed to compare the accuracy of RB to EM-NB in localizing and targeting pulmonary lesions in a porcine lung model. Four operators were tasked with navigating to four pulmonary targets in the outer periphery of a porcine lung, to which they were blinded, using both the RB and EM-NB systems. The dependent variable was accuracy. Accuracy was measured as a rate of success in lesion localization and targeting, the distance from the center of the pulmonary target, and by anatomic location. The independent variable was the navigation system, RB was compared to EM-NB using 1:1 randomization. Of 75 attempts, 72 were successful in lesion localization and 60 were successful in lesion targeting. The success rate for lesion localization was 100% with RB and 91% with EM- NB. The success rate for lesion targeting was 93% with RB and 80% for EM-NB. RB demonstrated superior accuracy in reaching the distance from the center of the lesion, at 0.62mm compared to EM-NB at 1.28mm (p = 0.001). Accuracy was improved using RB compared to EM- NB for lesions in the LLL (p = 0.025), LUL (p < 0.001), and RUL (p < 0.001). Our findings support RB as a more accurate method of navigating and localizing small peripheral pulmonary targets when compared to standard EM-NB in a porcine lung model. This may be attributed to the ability of RB to reduce substantial tissue displacement seen with standard EM-NB navigation. As the development and application of RB advances, so will the ability to accurately diagnose small peripheral lung cancer nodules, providing patients with early-stage lung cancer the best possible outcomes.

Improving lung cancer health equity by applying deep learning to low dose CT screening of minority and disadvantaged patients.

1584 Background: In the US, disparities in lung cancer mortality exist for African American, Hispanic, and other minorities. Standard of care low dose CT screening (LDCT) detects early-stage disease and improves mortality, yet disparities are perpetuated in screening by eligibility criteria derived from cohorts underrepresenting these minorities. One such cohort is the National Lung Screening Trial (NLST) cohort which is 92% White. Consequently, guidelines for lung cancer screening may be insufficient to address the unique needs of diverse populations. We hypothesize that Artificial Intelligence prediction of future lung cancer risk from an individual’s LDCT can partially mitigate racial and ethnic disparities and improve health system practice guidelines by individualizing screening risk as compared to current general guidelines. Here, we benchmark a Resnet18 3D neural network trained on NLST LDCT images, Sybil, on the diverse patient population of the University of Illinois Health system (UIH) which is 20% White and 60% African American. Methods: A real-world cohort from UIH consisting of 1,450 CT studies was evaluated alongside 60,378 CT studies from the NLST cohort. All CT studies evaluated by the model were not used in model training. Using Youden’s J index as a probability cutoff, sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were evaluated. Receiver operating characteristic (ROC) and precision-recall (PR) curves were generated to assess model performance between cohorts. NLST data were truncated to achieve equivalent incidence of lung cancer with UIH when generated PR curves. Results: Multi-year prediction performance (ROC-AUC and PR-AUC) between cohorts are summarized (Table). For prediction of lung cancer within 1-year of LDCT in the UIH cohort, the model respectively demonstrated sensitivity, specificity, positive predictive value, and negative predictive value among White (0.80, 0.77, 0.54, 0.92), African American (0.84, 0.78, 0.39, 0.97) races and Hispanic (0.75, 0.73, 0.60, 0.84) and non-Hispanic (0.87, 0.77, 0.42, 0.97) ethnicities. Conclusions: Model performance was similar between the NLST (92% White) and a diverse, real-world cohort at UIH (20% White) though decreases in ROC-AUC performance in year 1 predictions and may be due to insufficient representation of minority populations during model training. Prospective studies involving larger and more representative patient populations should be conducted to further optimize the model and evaluate its clinical utility to improve lung cancer health equity in minority populations.[Table: see text]

Lung cancer among patients with secondhand smoke exposure: A systematic review.

e22506 Background: Smoking tobacco is recognized as the leading cause of lung cancer. However, it is imperative to note that 10–15% of lung cancer patients have no history of smoking, and that lung cancer remains the leading cause of cancer deaths among non-smokers. Since passive smokers are exposed to many carcinogenic compounds in the exhaled smoke, it is naturally plausible that secondhand smoking (SHS) is a risk factor for lung cancer. However, current USPSTF screening guidelines for lung cancer with low dose CT (LDCT) do not include patients exposed to SHS. We performed a systematic review to highlight SHS as an etiology of lung cancer and insights for inclusion in cancer screening criteria. Methods: We utilized the PubMed, Medline, Science Direct, and ClinicalTrials.gov databases to search for relevant literature using keywords ('low Dose CT,' 'secondhand smoke,' 'lung cancer'). The search strategy was designed to ensure a comprehensive retrieval of pertinent literature, minimizing the possibility of omitting articles due to insignificant spelling and/or semantic variations. Eligible studies had to be published between 2010 and 2023 and focused on examining the effect of SHS in populations at risk of lung cancer or those undergoing lung cancer screening. Articles not available in English were excluded from this systematic review. In total, 239 relevant articles were retrieved from all databases, narrowing down to 14 articles after the initial screening and further reducing to 4 articles after the second round of screening. Results: Three of the four articles included in our systemic review were conducted in Asia. A study by He et al. showed a substantial increase in the relative risk of lung cancer among SHS (RR 2.00; 95% CI, 0.62-6.40), with significant dose-response relationships between cumulative SHS exposure at home and work and the increased risk of cause-specific and total mortality. Another observational study on the use of LDCT in Japan has interestingly shown a shifting landscape of lung cancer demographics, with 49.6% of patients identified as never-smokers and 70.0% of the never-smoker lung cancer patients having SHS exposure. Secondhand smoking has also been reported to increase the risk of pulmonary nodules (HR 1.17; 95% CI, 1.01-1.35) and pulmonary emphysema (OR 13.6; 95% CI, 1.70-106.1) in those with moderate-to-high SHS exposure, which was the population where lung cancer was more prevalent. Conclusions: Our findings suggest a critical gap in current healthcare recommendations, specifically addressing the absence of guidelines for LDCT screening in individuals with moderate-to-high SHS exposure despite established evidence linking SHS to a significant increase in the risk of lung cancer development. More studies are needed to formulate evidence-based guidelines for lung cancer screening and detection in this population, given the expected mortality reduction benefit.

Participant adherence in a lung cancer screening (LCS) program in a non-smoking population.

10556 Background: LCS guidelines in smoking populations includes an annual low-dose CT Chest (LDCT) scan. Historically, real-world adherence to repeat imaging following the baseline LDCT has been low at 22% (Silvestri et al. Chest 2023). Various reasons for non-adherence have been cited and can be amplified in populations where English is not the primary language, low health literacy, or logistical reasons that interfere with scheduling. We are conducting the Female Asian Nonsmoker Screening Study (FANSS), which is a pilot study for Asian women with no smoking history to provide LDCTs to this population. We describe the strategies utilized to address potential barriers to adherence and report the participant (pt) adherence observed to date for this population. Methods: FANSS is an IRB-approved trial that provides LDCTs annually for 3 years and has an interim follow-up phone call every 6 months. All aspects of the study other than the LDCT could be conducted virtually pending pt preference. All pt interactions were conducted in the pt’s requested language. LDCTs were interpreted according to Lung-RADS. Review of the LDCT results were available in-person or virtually by a nurse practitioner or the principal investigator. The timeline for the 2nd and 3rd LDCT after the baseline scan was determined as follows: pts with negative findings were recommended for a repeat LDCT in 1 year; pts with suspicious findings were reviewed at the NYU Multidisciplinary Nodule Board and recommended for a repeated LDCT in a 3 or 6 month interval. A bilingual (English and Chinese speaking) research coordinator and medical secretaries reached out to pts at their preferred contact (email, phone, or text) for scheduling the follow-up LDCT. Up to three attempts to reach pts to schedule their follow-up LDCT were made. Results: From 3/5/21 to 1/27/24, 634 subjects completed their baseline LDCTs. Language interpretation services were utilized in 30% of pts. As of 1/27/24, 215 pts were due for their 2nd LDCT: 195 (91%) completed (186) or scheduled (9) the LDCT, 5 pts withdrew their consent, and 15 did not complete the scan. The main reasons for not completing the scans were: living outside New York City, other health concerns, and lost to follow-up. As of 1/27/24, 95 pts were due for their 3rd LDCT: 87 (92%) completed (82) and scheduled (5) the LDCT, and 8 did not complete the scan due to being lost to follow-up. Conclusions: The FANSS population is a unique pt cohort comprised of all Asian women who do not qualify for current LCS guidelines. Interventions to address potential adherence issues were implemented. In our research-based setting, virtual conduct of most of the study procedures allowed pt flexibility. Pt outreach to ensure follow-up by contacting through various methods also ensured adherence of &gt;90%. These interventions can be considered for use in other LCS programs to improve adherence to LCS follow-up.

E-cigarette use and United States Preventive Services Task Force (USPSTF) lung cancer screening (LCS) eligibility.

10531 Background: Electronic cigarettes (E-cigarettes) have become frequently used as a smoking cessation tool. Emerging research has shown that e-cigarettes have similar carcinogenic effects as combustible cigarettes. While current lung cancer screening (LCS) guidelines primarily rely on individuals’ smoking history, it's becoming increasingly important to understand the prevalence of e-cigarette use among individuals, especially in the context of their LCS eligibility. Methods: Individuals aged 40-80 years were extracted from the 2022 Behavioral Risk Factor Surveillance System. Eligibility was defined using the 2021 USPSTF LCS criteria, i.e., aged 50-80 years who ever smoked, with at least a 20-pack-year smoking history, currently smoke or quit within the past 15 years. We compared the prevalence of current and ever e-cigarette use among LCS-eligible and non-eligible populations, overall and by smoking (combustible cigarettes) status using chi-square tests. All analyses were weighted. The significance level was set at a 2-sided p-value of &lt;0.05. Results: Among the 208,317 individuals included, 9.9% were eligible for LCS. Overall, 3.8% and 22.1% reported current and ever cigarette use, respectively. Fewer LCS-ineligible individuals reported currently using e-cigarettes than their LCS-eligible counterparts (Table). Among former combustible cigarette users, LCS-ineligible individuals were less likely to be current e-cigarette user than LCS-eligible individuals. However, among current combustible cigarette users, LCS-ineligible individuals were more likely to be current e-cigarettes users than LCS-eligible individuals. When examining the prevalence of ever e-cigarette use, similar findings were observed. Conclusions: Our study reveals a significant prevalence of e-cigarette usage among older adults (aged 40-80), with 1 in 5 individuals reporting ever having used e-cigarettes. Moreover, current cigarette users who were ineligible for LCS were more likely to use e-cigarette than their LCS-eligible counterparts. Future epidemiological studies are warranted to assess the risk of e-cigarette use (including intensity, duration and interactions with combustible cigarettes) and lung cancer risks. E-cigarette use may need to be considered in formulating future LCS guidelines. [Table: see text]

Characteristics of lung cancer screening eligible population in the US and prediction of the eligibility with simplified criteria.

In 2021, updates to the lung cancer screening (LCS) guidelines extended the eligibility to include younger individuals and those with lower lifetime smoking intensity. A significant challenge in the LCS implementation is identifying eligible individuals because lifetime smoking intensity, a key criterion of current guidelines, is typically unavailable in electronic health records and difficult to assess accurately. This study aimed to (I) examine the characteristics of the eligible population in the US based on current guidelines and (II) evaluate the performance of five simplified criteria as alternative tools for predicting LCS eligibility. National Health and Nutrition Examination Survey (NHANES) 2013-2018 data were used. Five simplified criteria were: (I) ever smoker, defined as an individual with any positive smoking history; (II) current or former smoker, an individual with any positive smoking history or who quit smoking within 15 years; (III) current smoker, an individual currently smoking; (IV) current smoker, an individual currently smoking >0.5 packs per day (ppd); (V) current smoker, a person currently smoking >1 ppd. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were calculated. The complex survey design was considered. About 16.70 million individuals (representing 16.01% of population aged 50-80 years) were eligible for LCS in the US. The percentage of LCS eligibility was higher among people who were younger, male, non-Hispanic White, less educated, single, not insured, with poorer health status and lower socioeconomic status. Except for the criterion of current smoker with >1 ppd having low sensitivity (0.08), other criteria had sensitivity ranging between 0.45 and 1.00. The accuracy of the five criteria used ranged between 0.70 and 0.91. Individuals with less favorable social and clinical characteristics have higher chances of being eligible for LCS, potentially amplifying disparities in LCS utilization. Simplified criteria can be used as prescreening tools to identify target populations, which could facilitate LCS implementation at the population level.

Results of Lung Cancer Screening with Low-dose Computed Tomography and Exploration of Risk Factors in Guangzhou

Both of lung cancer incidence and mortality rank first among all cancers in China. Previous lung cancer screening trials were mostly selective screening for high-risk groups such as smokers. Non-smoking women accounted for a considerable proportion of lung cancer cases in Asia. This study aimed to evaluate the outcome of community-based mass screening in Guangzhou and identify the high-risk factors for lung cancer. Residents aged 40-74 years in Guangzhou were screened with low-dose computed tomography (LDCT) for lung cancer and the pulmonary nodules were classified and managed according to China National Lung Cancer Screening Guideline with Low-dose Computed Tomography (2018 version). The detection rate of positive nodules was calculated. Before the LDCT examination, residents were required to complete a "lung cancer risk factors questionnaire". The risk factors of the questionnaire were analyzed by least absolute shrinkage and selection operator (LASSO) penalized Logistic regression analysis. A total of 6256 residents were included in this study. 1228 positive nodules (19.63%) and 117 lung cancers were confirmed, including 6 cases of Tis, 103 cases of stage I (accounting for 88.03% of lung cancer). The results of LASSO penalized Logistic regression analysis indicated that age ≥50 yr (OR=1.07, 95%CI: 1.06-1.07), history of cancer (OR=3.29, 95%CI: 3.22-3.37), textile industry (OR=1.10, 95%CI: 1.08-1.13), use coal for cooking in childhood (OR=1.14, 95%CI: 1.13-1.16) and food allergy (OR=1.10, 95%CI: 1.07-1.13) were risk factors of lung cancer for female in this district. This study highlighted that numerous early stages of lung cancer cases were detected by LDCT, which could be applied to screening of lung cancer in women. Besides, age ≥50 yr, personal history of cancer, textile industry and use coal for cooking in childhood are risk factors for women in this district, which suggested that it's high time to raise the awareness of early lung cancer screening in this group.

Screening for Lung Cancer in India: Expert Opinion Statement.

Lung cancer (LC) has the highest rate of disability-adjusted life years (DALY) of all cancers in India. A large majority of patients with LC present with advanced disease, resulting in poor survival rates. Early diagnosis can improve survival outcomes as the patients can be treated with curative intent. The National Lung Screening Trial (NLST), in 53,454 persons at high risk for LC in the US, showed a 20% (95% confidence interval of 6.8-26.7; p = 0.004) relative reduction in LC-specific mortality in the patients screened with low-dose computed tomography (LDCT) compared with chest X-ray. To date, India does not have a formal LC screening (LCS) program. As a panel of experts, we reviewed a synthesis of a targeted literature search on the burden of LC, the current status of diagnosis of LC, barriers to early diagnosis, current referral pathways, LC risk patterns, use of artificial intelligence (AI) and risk calculators for risk assessment, and a multidisciplinary team (MDT) approach to diagnosis LC. We used the existing international LCS guidelines, data from published literature, and clinical experience to depict the characteristics of the population at risk of LC in India-young age (<40 years), smoking, especially the predominance of bidi smoking (an indigenous form of tobacco smoking), exposure to biomass fuel smoke, especially in rural women, and air pollution being the prominent features. LC in India is characterized by a higher rate of driver mutations and adenocarcinomatous histology. Here, we present the expert opinion on risk-based LCS in India and discuss the challenges, facilitators, and research priorities for the effective rollout of LCS in India.

Geographic Accessibility and Completion of Initial Low-Dose CT-Based Lung Cancer Screening in an Urban Safety-Net Population.

Recent modifications to low-dose CT (LDCT)-based lung cancer screening guidelines increase the number of eligible individuals, particularly among racial and ethnic minorities. Because these populations disproportionately live in metropolitan areas, we analyzed the association between travel time and initial LDCT completion within an integrated, urban safety-net health care system. Using Esri's StreetMap Premium, OpenStreetMap, and the r5r package in R, we determined projected private vehicle and public transportation travel times between patient residence and the screening facility for LDCT ordered in March 2017 through December 2022 at Parkland Memorial Hospital in Dallas, Texas. We characterized associations between travel time and LDCT completion in univariable and multivariable analyses. We tested these associations in a simulation of 10,000 permutations of private vehicle and public transportation distribution. A total of 2,287 patients were included in the analysis, of whom 1,553 (68%) completed the initial ordered LDCT. Mean age was 63 years, and 73% were underrepresented minorities. Median travel time from patient residence to the LDCT screening facility was 17 minutes by private vehicle and 67 minutes by public transportation. There was a small difference in travel time to the LDCT screening facility by public transportation for patients who completed LDCT versus those who did not (67 vs 66 min, respectively; P=.04) but no difference in travel time by private vehicle for these patients (17 min for both; P=.67). In multivariable analysis, LDCT completion was not associated with projected travel time to the LDCT facility by private vehicle (odds ratio, 1.01; 95% CI, 0.82-1.25) or public transportation (odds ratio, 1.14; 95% CI, 0.89-1.44). Similar results were noted across travel-type permutations. Black individuals were 29% less likely to complete LDCT screening compared with White individuals. In an urban population comprising predominantly underrepresented minorities, projected travel time is not associated with initial LDCT completion in an integrated health care system. Other reasons for differences in LDCT completion warrant investigation.

Abstract 981: Robustness of fragmentation-based cell-free DNA approaches to clonal hematopoiesis

Abstract INTRODUCTION: Clonal hematopoiesis (CH) is the result of the clonal expansion of hematopoietic stem cells which acquire and pass on somatically gained mutations, including SNVs as well as arm level losses and gains, defined here as mosaic deletions and amplifications (mDAs). The proportion of blood cells in circulation containing CH alterations increases with age and environmental exposures such as smoking, leading to a higher prevalence in many high-risk cancer screening populations. CH remains a major confounder for mutation-based liquid biopsy tests evaluating circulating cell-free DNA (cfDNA), since these assays are unable to discriminate between mutations originating from the tumor as opposed to CH. While the impact of CH mutations on fragmentation-based methods of detecting ctDNA appears to be limited, the effect of mDAs has not yet been explored. METHODS: To assess the impact of mDAs on screening efforts using whole genome sequencing (WGS) of cfDNA, we performed copy number analyses on cfDNA from plasma collected from 895 individuals consisting of high-risk individuals meeting the USPSTF guidelines for annual lung cancer screening using low-dose computed tomography. From a subset of 203 available donors (157 without cancer and 46 with lung cancer), matched genomic DNA from white blood cells (WBCs) were extracted from the isolated buffy coat and WGS was performed to evaluate whether ploidy in cfDNA plasma is derived from WBCs. Genome-wide fragmentation features (short to long ratios and fragment size densities), coverage-based statistics, and copy number (CN) statistics adjusting for mDAs were calculated (CNadj). Machine learning models to calculate the probability of cancer based on these features were then derived. RESULTS: 3.8% (95% CI 0.9%-6.8%) of individuals without cancer had an mDA in their WBCs that were also observed in the plasma (p &amp;lt; 0.01, permutation test). Fragmentation features were not different in regions with mDAs in individuals without cancer (p = 0.619; permutation test) but were altered in regions of tumor-derived chromosomal changes in patients with cancer (p &amp;lt; 0.01; permutation test). Coverage-based statistics were impacted by mDAs (p &amp;lt; 0.01; Wilcoxon test). Machine learning models fit with CNadj showed improved performance over CN. However, machine learning models fit with fragmentation features compensated for this difference overall showing robustness to mDAs (p = 0.45; bootstrap) demonstrating the robustness of cfDNA fragmentomes for detecting lung cancer. CONCLUSIONS: While coverage-based statistics of WGS analyses of cfDNA may be affected by mDAs, fragmentation-based approaches relying on cfDNA fragment length are robust to effects of CH. CNadj is an improved statistic for detecting tumor-derived chromosomal copy number changes in cfDNA, providing increased specificity by conditioning on fragment size distributions. Citation Format: Stephen Cristiano, Bahar Alipanahi, Jamie E. Medina, Lorenzo Rinaldi, Nicholas Dracopoli, Robert B. Scharpf, Alessandro Leal, Victor E. Velculescu, Jennifer Tom. Robustness of fragmentation-based cell-free DNA approaches to clonal hematopoiesis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 981.

Abstract 6075: Most cancer deaths are unaddressed by current screening paradigms

Abstract Cancer is the leading cause of death at ages ≤80 in the US. To understand the burden of cancer death potentially addressable by new or improved screening approaches, we estimated the proportion of US cancer deaths without recommended guideline-based screening, especially after accounting for lung cancer screening eligibility and adherence. Using 2018-2019 mortality data from the National Center for Health Statistics and published estimates of the proportion of screening-eligible lung cancer patients, we estimated that 31.4% of nearly 600,000 annual cancer deaths were from colorectal, female breast, cervical, and smoking-eligible lung cancers (Table). Further accounting for adherence to lung cancer screening guidelines reduced the estimated proportion of screened cancer deaths to 17.4%; thus, 82.6% of cancer deaths may not be addressed by current guideline-based screening. Among the cancers not covered by guideline-based screening are uncommon cancer types, which (as defined by the National Cancer Institute) comprised 30.4% of cancer deaths. According to incidence-based mortality data from Surveillance, Epidemiology, and End Results registries, 24.7% of all cancer deaths were from stage 4 cancer types without guideline-based screening. These estimates, based on population data without patient-level information on mode of diagnosis, almost certainly underestimate the percentage of cancer deaths missed by currently available screening efforts. The large proportion of cancer deaths unaddressed by guideline-based screening represents a vast opportunity for new cancer screening technologies that are safe, effective, accessible, and affordable to enable earlier detection and successful treatment of the full spectrum of cancer types that contribute to the overall cancer burden. Table. Deaths from cancer by primary type in 2018-2019, US National Center for Health Statistics, with eligibility for and adherence to guideline-based low-dose computed tomography screening for lung cancer All cancer types Lung Colon/rectum Breast (female) Uterine cervix Total screened % of all All cancer deaths 1,198,854 281,681 104,059 84,745 8,290 478,775 39.9% Eligible for screening based on smoking (63.7% of lung)* 179,431 104,059 84,745 8,290 376,525 31.4% Adherent to smoking-guideline-based screening (6.6% of lung)† 11,842 104,059 84,745 8,290 208,936 17.4% *Modeled estimate of proportion of lung cancer patients eligible for screening (Landy et al. 2023). †Lung cancer screening receipt from 2019 American College of Radiology Lung Cancer Screening Registry (Fedewa et al. 2022). Citation Format: Ellen T. Chang, Anuraag Kansal, Earl A. Hubbell, Graham A. Colditz, Allison W. Kurian, Christina A. Clarke. Most cancer deaths are unaddressed by current screening paradigms [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6075.

LDCT screening results among eligible and ineligible screening candidates in preventive health check-ups population: a real world study in West China

To compare the LDCT screening results between eligible and ineligible screening candidates in preventive health check-ups population. Using a real-world LDCT screening results among people who took yearly health check-up in health management center of West China Hospital between 2006 and 2017. Objects were classified according to the China National Lung Cancer Screening Guideline with Low-dose Computed Tomography (2018 version) eligibility criteria. Descriptive analysis were performed between eligible and ineligible screening candidates. The proportion of ineligible screening candidates was 64.13% (10,259), and among them there were 4005 (39.04%) subjects with positive screenings, 80 cases had a surgical lung biopsy. Pathology results from lung biopsy revealed 154 cancers (true-positive) and 26 benign results (false-positive), the surgical false-positive biopsy rate was 4.17%, and ineligible group (7.69%) was higher than eligible group (2.47%), P < 0.05. Further, in ineligible screening candidates, the proportion of current smokers was higher among males compared to females (53.85% vs. 4.88%, P < 0.05). Of the 69 lung cancer patients detected in ineligible screening candidates, lung adenocarcinoma accounts for a high proportion of lung cancers both in male (75.00%) and female (85.00%). The proportion of ineligible screening candidates and the surgical false-positive biopsy rate in ineligible candidates were both high in health check-ups population.

Acceptability of Personalized Lung Cancer Screening Program Among Primary Care Providers.

Personalized LCS facilitated by a risk model and/or a biomarker test is proposed as an alternative to existing programs. Acceptability of personalized approach among PCPs is unknown. The goal of this study is to assess the acceptability of personalized LCS among PCPs.

"They Need to Feel Non-Judgmental": Results of Participatory Photovoice Research to Inform Lung Cancer Screening Imagery.

Effective communication and messaging strategies are crucial to raise awareness and support participants' efforts to adhere to lung cancer screening (LCS) guidelines. Health messages that incorporate images are processed more efficiently, and given the stigma surrounding lung cancer and cigarette smoking, emphasis must be placed on selecting imagery that is engaging to LCS-eligible individuals. This exploratory study aimed to identify person-centered themes surrounding LCS imagery. This qualitative study leveraged a modified photovoice approach and interviews to define descriptive themes about LCS imagery. Study participants eligible for annual LCS who had a CT scan within 12 months were asked to select three images and participate in a semi-structured interview about photo selection, likes, and dislikes. Participants were also asked their opinions about images from current LCS communications featuring matches, smoke, and cigarettes. Data were analyzed using an inductive thematic approach. Data saturation was reached after thirteen individuals completed the photovoice activity; each participant selected three pictures resulting in a total of 39 images representing LCS. Over half (54%) of images selected contained lungs and only 4 (10%) contained smoking-related elements. Five main themes emerged: 1) images should focus on good news and early detection; 2) people should be relatable; 3) pictures with lungs can dually support lung health or invoke fear; 4) opportunity for education or awareness; and 5) should not be judgmental and induce stigma. These findings suggest that LCS imagery should not contain negative or stigmatizing elements but instead be relatable and educational. This information can inform communication and messaging interventions and strategies for future LCS participation, awareness, and educational research.