Abstract C135: Estimating lung cancer screening eligibility and utilization in Guam

Abstract Background: Lung cancer screening with low-dose computed tomography (LDCT) reduces mortality by detecting cancer at earlier, more treatable stages. In Guam, lung cancer is the second most common cancer and the leading cause of cancer death, accounting for 27.5% of all cancer fatalities. Only 16.4% of lung cancer cases are diagnosed at an early stage. Despite these figures, little is known about screening utilization or the size of the population eligible for screening under current U.S. Preventive Services Task Force (USPSTF) guidelines. Methods: This study estimated the number of Guam residents eligible for lung cancer screening and assessed screening utilization in 2022. Eligibility criteria included ages 50–80 years, a ≥20 pack-year smoking history, and current smoking or quitting within the past 15 years. Weighted eligibility estimates from the 2022 Guam Behavioral Risk Factor Surveillance System (BRFSS) were stratified by sex and applied to age- and sex-specific population counts from the 2020 Guam Census. Actual screening utilization was determined using records from the only LDCT screening provider on Guam in 2022. Results: There was a substantial gap between those eligible and those screened for lung cancer. An estimated 31.8% of males and 11.2% of females aged 50–80 met USPSTF eligibility, corresponding to approximately 9,186 residents (6,754 males; 2,432 females). However, only 1,436 individuals were screened, representing just 16% of the eligible population. Among those screened, 61.1% were male and 38.9% were female, with an average age of 64.3 years. Nearly half (48.5%) were covered by Medicare or Medicaid, 26.9% had private insurance, and 21.7% had missing or unlisted insurance information. Most had negative or benign results, with 62.3% classified as LUNG-RADS 1 or 1S and 24.9% as LUNG-RADS 2 or 2S; only 5.3% had indeterminate or suspicious findings requiring further follow-up. Conclusions: Despite significant eligibility, lung cancer screening is underutilized in Guam. Targeted efforts are needed to identify barriers and increase screening uptake, with the goal of improving early detection and reducing lung cancer mortality. Funding Source: This research was, in part, funded by the National Institutes of Health (NIH) Agreement NO. 1OT2OD032581. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the official policies, either expressed or implied, of the NIH. Citation Format: Cabrini Aguon, Angelika Argao, Isaac Berg, Nathaniel B. Berg, Lakshman Tamil, Grazyna Badowski. Estimating lung cancer screening eligibility and utilization in Guam [abstract]. In: Proceedings of the 18th AACR Conference on the Science of Cancer Health Disparities; 2025 Sep 18-21; Baltimore, MD. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2025;34(9 Suppl):Abstract nr C135.