Social Exposome and Thyroid Cancer Outcomes in a Population-Based Study

Background/Objectives: Thyroid cancer incidence has risen in recent decades, with emerging evidence that social determinants of health and environmental exposures contribute to geographic and population-level disparities in risk and outcomes. This study applies a social exposome perspective to characterize how community-level social and environmental factors shape thyroid cancer patterns. This work aims to examine how geospatial social exposome factors and environmental exposures influence thyroid cancer incidence and outcomes in a population-based context. Methods: Surveillance, Epidemiology, and End Results (SEER) registry data were analyzed to estimate thyroid cancer incidence by demographic and pathological characteristics. Multivariate regression and decision tree models were used to assess associations between social and environmental risk factors and thyroid cancer rates. Results: The age-adjusted thyroid cancer incidence was 15.5 per 100,000, with higher rates among younger adults, females, and white populations. Incidence was elevated in metropolitan and higher-income communities (p < 0.001). American Indian/Alaska Native individuals had a lower overall incidence but were more likely to present with advanced disease, whereas Black individuals had the lowest incidence but the poorest survival. Socioeconomic disadvantage was positively associated with thyroid cancer burden, while smoking cessation, fruit consumption, and higher ultraviolet (UV) exposure were protective. Conclusions: Thyroid cancer incidence is highest in affluent, metropolitan, predominantly white communities, likely reflecting greater access to screening and diagnostic services. At the same time, socially and economically underserved groups experience more advanced disease at diagnosis and worse survival. These findings underscore the importance of community-level, targeted prevention and early detection strategies that address social exposome factors and structural inequities in thyroid cancer care and outcomes.