Abstract Purpose: Obesity is a growing public health crisis and a known risk factor for several malignancies. Despite global evidence demonstrating a strong association between obesity and increased cancer incidence, region-specific data for Puerto Rico remain scarce. This study aims to characterize the burden and temporal trends of obesity-associated cancers among adults in Puerto Rico from 2000 to 2022. Methods: We analyzed invasive cancer cases diagnosed between 2000 and 2022 among adults aged ≥20 years using data from the Puerto Rico Central Cancer Registry. Obesity-associated cancers were defined according to the CDC criteria, including esophageal adenocarcinoma, gastric cardia, colorectal, liver, gallbladder, pancreas, multiple myeloma, postmenopausal female breast, corpus and uterus (not other specified), ovary, kidney, meningioma, and thyroid cancers. Age-adjusted incidence rates for 2018–2022 were calculated using the direct method, standardized to the 2000 U.S. standard population. Temporal trends in incidence were assessed using joinpoint regression analysis to estimate Annual Percent Changes (APCs) and Average Annual Percent Changes (AAPCs), stratified by sex and age group. Data from 2020 were excluded from trend analyses due to disruptions related to the COVID-19 pandemic. Results: Between 2018 and 2022, a total of 35,468 cases of obesity-associated cancers were reported, yielding an overall age-adjusted incidence rate of 213.18 per 100,000 population. From 2000 to 2022, the incidence of obesity-associated cancers increased significantly (AAPC: 1.4%, p 0.05), with the steepest rise observed among adults aged 50 years (AAPC: 4.6%, p 0.05). Among women, those under 50 experienced the highest increase (AAPC: 4.9%), compared to older women (AAPC: 1.0%) and men in both age groups (AAPC: 3.9% for 50 years; 0.7% for ≥50 years). By cancer type, the largest increases in AAPC were observed among adults aged 40–49 years, particularly for pancreatic cancer (9.53%) and multiple myeloma (9.09%). Within this age group, women had a substantially higher AAPC for pancreatic cancer (12.87%) compared to men (4.94%), whereas men had higher AAPCs for multiple myeloma (11.67%) and thyroid cancer (9.12%). Conclusions: The incidence of obesity-associated cancers is rising at an alarming rate in Puerto Rico, with the most substantial increases observed among women aged 40–49 years. These findings underscore an urgent public health concern and highlight the need for targeted prevention strategies. Efforts should prioritize the promotion of a healthy lifestyle, obesity prevention and management, and the early identification of individuals at elevated risk to mitigate the projected cancer burden on the island. Citation Format: Carola T. Sánchez-Díaz, Génesis Rodríguez-Ortiz, Valeria S. Rivera-Alvarado, Carlos R. Torres-Cintrón, Jan C. Gómez-Pérez, Cynthia M. Pérez-Cardona, Karen J. Ortiz-Ortiz. Temporal trends in the incidence of obesity-associated cancers in Puerto Rico, 2000–2022: Disproportionate increases among younger adults 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 B133.
Sánchez-Díaz et al. (Thu,) studied this question.