Abstract A135: Rural-urban trends in ovarian cancer incidence among women aged 20-84 in the United States, 2000-2019

Abstract Purpose: To characterize rural-urban disparities of ovarian cancer incidence trends by stage, race/ethnicity, and poverty Background: In the United States (US), ovarian cancer (OC) affects ∼20,000 women annually, with 13,000 deaths each year. OC incidence has declined by about 1-2% annually since the early 1990s but less is known about how trends may vary by rurality. Rural women often experience health care barriers related to geographic isolation, lower access to specialty care, and higher rates of cancer risk behaviors compared to urban residents, potentially leading to delayed diagnosis. Furthermore, trends may also differ for women from racial/ethnic minority groups or those who live in socioeconomically disadvantaged areas. Methods: We used cancer incidence data from the North American Association of Central Cancer Registries (NAACCR) to identify women aged 20-84 with incident ovarian cancer from 2000-2019 in the US, stratified by county-level rurality (2013 USDA Beale Rural-Urban Continuum Codes), race/ethnicity (Hispanic, Non-Hispanic NH White, NH Black, NH Other), and census-tract poverty (10%, ≥10%). Age-adjusted incidence rates (IR) 2000 US Standard Population and trends were identified using the Joinpoint Regression Program. We reported both the annual percentage change (APC) and average annual percentage change (AAPC). Results: Among 359,786 cases, 84.7% of the cases occurred in urban counties (15.3% rural). IRs were similar between urban and rural counties (IRurban=14.8, IRrural=14.1 cases per 100,000 people). OC in urban counties decreased by -1.41%/yr (APC2000-2019=AAPC=-1.41, 95% CI: -1.76, -1.44). Cases decreased by -1.10%/yr from 2000-2014 (APC=-1.10 -1.37, -0.65) in rural counties, and more rapidly in later years (APC2014-2019=-3.30 -6.15, -2.14). Distant stage OC decreased in rural counties from 2014-2019 (APC=-7.25 -11.99, 5.34), but localized OC increased after 2005 (APC2005-2019=+2.34 [1.05, 4.46). Trends for localized and regional OCs in urban counties fluctuated every few years but were otherwise stable throughout the study period. Distant stage OCs in rural counties decreased overall (AAPC=-2.79 -3.16, -2.51). While trends decreased for all groups, IRs declined faster for urban, NH White women (APC2015-2019=-3.12 -5.58, -2.09) than NH Black women (APC2013-2019=-2.28%, -5.04, -1.19). The results were similar by race for rural counties. The IRs decreased regardless of poverty level, but IRs were higher in urban vs. rural counties with low poverty (10%, IRurban=8.0, IRrural=3.5) while the opposite was true for high poverty areas (≥10%, IRurban=6.4, IRrural=9.5). Conclusions: OC IRs decreased in both urban and rural areas over time, but disparities persist by stage, race/ethnicity, and poverty. Current literature suggests the overall decline may be due to trends in oral contraceptives and hormone therapy use, but more research is needed to understand the underlying drivers of OC risk, early-detection, and treatment access disparities in rural vs. urban settings. Citation Format: Katherine L. Ho, Michael R. Desjardins, Kassandra I. Alcaraz, Avonne E. Connor. Rural-urban trends in ovarian cancer incidence among women aged 20-84 in the United States, 2000-2019 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 A135.