S2464 Rising Incidence of Liver Cancer Among Older Adults in the United States (1999-2019): Disparities by Sex, Race/Ethnicity, and Region

Introduction: Liver cancer incidence has been increasing in the United States, particularly among older adults. Understanding demographic and regional variations is crucial for developing targeted interventions and resource allocation strategies. This study examined trends in age-adjusted incidence rates (AAIR) of liver cancer among individuals aged 65 years and older from 1999 to 2019. Methods: We utilized the United States Cancer Statistics (USCS) Public Use Database (1999–2019) to identify incident liver cancer cases in adults aged ≥65 years. Incidence rates were age-adjusted to the 2000 U.S. standard population and expressed per 100,000 persons. Analyses were stratified by sex, race/ethnicity, and region. Joinpoint regression was used to calculate the Annual Percent Change (APC) for each identified trend segment and the Average Annual Percent Change (AAPC) over the entire study period. Results: Overall AAIR nearly doubled from 17.99 (95% CI: 17.55–18.45) in 1999 to 34.01 (95% CI: 33.51–34.51) in 2019 (AAPC: 3.21%; 95% CI: 3.13–3.31). During this time, men consistently exhibited higher incidence (27.49 to 53.66) compared to women (11.33 to 17.99), with corresponding AAPCs of 3.38% and 2.26%, respectively. Among racial/ethnic groups, American Indian/Alaska Native (AI/AN) populations showed the largest relative increase (30.41 to 61.70; AAPC: 3.67%), while Black or African American individuals also had a significant rise (21.62 to 40.88; AAPC: 3.58%). Hispanic populations experienced an increase from 41.99 to 62.29 (AAPC: 2.05%). In contrast, Asian or Pacific Islander groups demonstrated a slight decline in incidence (56.15 to 50.58; AAPC: -0.75%). Regionally, the West had the highest AAIR in 2019 (37.82), whereas the South exhibited the steepest overall increase (16.59 to 35.76; AAPC: 3.86%). The Northeast (19.21 to 31.51; AAPC: 2.46%) and Midwest (15.97 to 29.10; AAPC: 2.96%) both experienced steady upward trends, underscoring the widespread growth in liver cancer incidence among older adults across all U.S. regions. Conclusion: Liver cancer incidence among U.S. adults aged ≥65 years has continued to rise substantially over the past 2 decades, with marked disparities by sex, race/ethnicity, and region. These findings highlight the need for tailored prevention, screening, and management strategies, especially in high-risk groups such as AI/AN and Black populations and in regions with rapidly increasing rates.