Abstract
BACKGROUND: Unique features and worse outcomes have been reported for breast cancers among adolescents and young adults (AYAs; age 15-39 years). However, there are few up-to-date and comprehensive data to analyze the disease burden of AYA breast cancer. PATIENTS AND METHODS: The data of incidence, deaths, and disability-adjusted life years (DALYs) owing to breast cancer was obtained from the Global Burden of Disease (GBD) 2021. We computed estimated annual percentage changes (EAPCs) of each indicator to capture the secular trend in breast cancer and conducted a decomposition analysis to examine factors behind DALYs changes. We also predicted the incident cases, deaths and DALYs to 2044. RESULTS: From 1990 to 2021, the age-standardized incidence rate (ASIR) experienced an increasing trend globally [EAPC: 0.87, 95% confidence interval (CI) 0.77-0.97]. The age-standardized rates (ASRs) of male AYAs breast cancer were all on the rise. The most significant increase trends in ASRs among female AYAs occurred in North Africa and Middle East, while male AYAs showed the highest increases in East Asia. Population growth contributed the most to the growth of DALYs in East Asia. Frontier analysis showed that despite limited resources, some underdeveloped countries still exhibit superior performance, while other countries with higher sociodemographic index have great room for improvement. CONCLUSIONS: The global burden of AYAs breast cancer is grim, especially in North Africa and Middle East. The significant increase in male AYAs breast cancer burden, targeted prevention strategies may need to be developed for AYAs breast cancer by sex and countries.