Abstract IA-13: Using large, prospective cohort data to elucidate sexual orientation-related cancer disparities

Abstract

Abstract Nearly half of U.S. men and women will develop cancer in their lifetime, but certain groups, such as sexual minorities (e.g., lesbian, gay, bisexual [LGB] individuals), may be at greater risk. For almost 20 years, the Institute of Medicine has warned of a potential elevated cancer risk among sexual minorities because known risk factors—nulliparity, obesity, smoking, alcohol use—are more common than among heterosexuals. However, national cancer registries do not collect sexual orientation, so there is no way to quantify the magnitude of this burden. Without these data, sexual minorities may continue to be disproportionately burdened by cancers. Longitudinal cohort studies with substantial statistical power and high-quality assessments of sexual orientation and cancer endpoints are the best way to fill this gap. Such studies will provide the empirical evidence needed to develop public health interventions and offer data that are not feasible for cancer registries to collect, such as self-reported dietary intake. This grant's goal is to quantify cancer disparities with longitudinal cohort data and, using a life course framework, gain a nuanced understanding of factors across the lifespan, which may confer different risk in various sexual orientation groups. To address these gaps, we analyzed national data from four longitudinal cohorts: the Nurses' Health Study (NHS) 2 and 3 and the Growing Up Today Study (GUTS) 1 and 2. These cohorts include nearly 200,000 male and female participants, 8% (or nearly 15,000) of whom are sexual minorities, giving ample statistical power. The data span from the prenatal period through adulthood and include detailed sexual orientation measures and biospecimens as well as thousands of cancer cases, including hundreds in sexual minorities. With these data, we can provide more accurate estimates of cancer incidence across sexual orientation groups and a more nuanced understanding of mediating risk factors. The findings will highlight new avenues for health equity and interventions for all people, regardless of sexual orientation. Citation Format: Brittany Charlton. Using large, prospective cohort data to elucidate sexual orientation-related cancer disparities [abstract]. In: Proceedings of the AACR Virtual Conference: 14th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2021 Oct 6-8. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr IA-13.