Abstract A123: Sex-based differences in head and neck cancer risk: Evidence from the All of Us research program

Abstract Introduction Historic differences in sex-based differences in head and neck cancer (HNC) risk factors, such as lifestyle behaviors and health care access, existed influencing HNC incidence. It remains unclear whether historic differences continue to persist which impacts tailored cancer prevention methods. Hypothesis/Objectives Examine sex-based differences in HNC risk factors within the All of Us Research Program. Methods The All of Us Research Program fully enrolled 849,000 participants between 2018 and 2024. 452,000 consented to share their electronic health records. Among them, we identified 1,099 individuals diagnosed with HNC based on ICD-9 and ICD-10 codes and with complete data on sociodemographic (age at diagnosis and race/ethnicity), lifestyle behaviors (including ever smoking cigarettes, age at smoking initiation, years smoked, smoking duration, cigarettes per day, smoking intensity, use of alternative tobacco products, and alcohol consumption), dental care access (ever attended a dental appointment) and family cancer history. We conducted bivariate tests between HNC risk factors and sex using Chi-square, ANOVA, and t-tests. We ran a Cox regression model that retained variables significant at p0.05. Analyses were conducted between December 2024 and Jun 2025 using RStudio (VERSION 4.4.2). Results: Participants included 41% women and 57% men with a mean age at diagnosis of 60.7 (12.5) years. Most participants identified as non-Hispanic White, with 90% reporting ever consuming alcohol and 49% having ever smoked, with an average smoking duration of 25.1 (15.1) years. Compared to men, women were diagnosed at a significantly younger age (mean (SD): 57.5 (14) vs. 63 (11); p 0.001), were less likely to be non-Hispanic White (p = 0.027), less likely to be ever drinkers (p 0.001), less likely to be ever smokers (p 0.001), and less likely to use alternative tobacco products (p 0.001).We observed no significant sex differences in dental care access or family history of cancer. In the fully adjusted multivariable logistic regression model, we observed no statistically significant differences in HNC risk factors by sex. Conclusions We observe no difference in sex and HNC risk factors; suggesting that exposure-related risk factors no longer differ between sex in contemporary cohorts. Citation Format: Nathalia Felix de Mendonca, Jasmine A. McDonald. Sex-based differences in head and neck cancer risk: Evidence from the All of Us research program 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 A123.