Abstract 2315: Projecting lung cancer incidence in Guam: the impact of smoking prevalence, ethnic disparities, and aging population

Abstract Lung cancer incidence in Guam is slightly lower than in the U.S. overall (50.9 vs. 52.6 per 100, 000), but CHamoru and Micronesian populations have significantly higher rates (69.4 and 78.6 respectively). Given the established link between smoking and lung cancer, this study aims to project lung cancer incidence in Guam considering smoking rates across sex, age, and ethnic groups, accounting for the island's aging population (median age increased from 30.4 in 2010 to 33.7 in 2020). Data on 1, 157 invasive lung cancer cases reported to the Guam Cancer Registry from 2001 to 2020 for individuals aged 34 and older were analyzed. Variables included age, sex, and ethnicity including CHamoru (52.3%), Filipino (20.9%), Micronesian (9.4%), Asian (6.4%), and White (7%). Smoking prevalence data from the 2011-2020 Behavioral Risk Factor Surveillance System (BRFSS) were used to estimate smoking rates for age × sex × ethnicity strata. A Poisson regression model was used to examine relationships between lung cancer incidence rates and demographic factors, including strata-level smoking prevalence. Temporal trends were evaluated across two periods: 2001-2010 and 2011-2020. Predicted rates were applied to 2020 Guam Census population counts to estimate lung cancer cases for 2021-2030 and the annual percent change (APC). From 2011 to 2020, smoking prevalence in Guam declined from 30.2% to 19% (APC = -3.7), with variation among ethnic groups. CHamoru and Asian males had the highest smoking rates. Micronesians showed the largest decrease (APC = -7.3%, from 35% to 10%), while CHamoru males had the smallest reduction (APC = -2.8%, from 46% to 35%). Lung cancer incidence was significantly higher for individuals aged 75+ compared to those aged 35-44 (IRR = 38, 95% CI: 26.9, 55). Males had over twice the rate of females (IRR = 2.3, 95% CI: 2.0, 2.7). Micronesians and CHamorus had significantly higher rates than Filipinos (IRR = 3.5 and 2.4, respectively). Each unit increase in smoking prevalence was associated with a 2% rise in lung cancer incidence for Micronesians and CHamorus. Projected lung cancer cases over 10 years are highest among CHamoru males (246) and females (130). The model predicts annual increases of 1.2% for males and 0.5% for females, with the largest increases among Asian males (2.6%) and Micronesian females (3.3%). Significant differences in lung cancer and smoking rates exist, with the highest burden among CHamorus and Micronesians. Despite a decrease, Guam's 2020 smoking prevalence remained significantly higher than the U.S. average of 12.5%, indicating persistent disparities. This study highlights the need for targeted tobacco control interventions and screening programs to address the evolving cancer burden. This research was funded by the National Cancer Institute Grant: U54CA143728 (University of Guam)/Grant U54CA143727 (University of Hawaii Cancer Center). Citation Format: Cabrini Cruz Aguon, Grazyna Badowski, Aurienne Cruz, Grace G. Bordallo. Projecting lung cancer incidence in Guam: the impact of smoking prevalence, ethnic disparities, and aging population [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 2315.