National and Subnational Burden of Female Breast Cancer in Iran from 2010 to 2021

<i>Background and Objectives</i>: Female breast cancer (FBC) is an increasing public health concern in Iran, with notable geographic disparities that necessitate comprehensive burden assessments at national and provincial levels. This study presented the national and subnational burden and changes in FBC burden from 2010 to 2021 in Iran in comparison with global data. <i>Materials and Methods</i>: The GBD (2021) data on female BC were extracted from the Global Health Data Exchange (GHDx) query tool. Age-standardized incidence, deaths, prevalence, and adjusted years of life with disabilities (DALYs) rates (per 100,000) of FBC were extracted. Data were extracted globally, by continents, for Iran and its provinces, from 2010 to 2021. <i>Results</i>: Although the global FBC burden indicators remained almost stable, in Iran, there was a nearly twofold rise in incidence and prevalence and notable rises in mortality and DALYs. This study showed significant variation at the provincial level; Tehran, Qom, and Alborz consistently had the highest incidence, prevalence, mortality, and DALY rates, whereas Sistan and Baluchistan, Chahar Mahaal and Bakhtiari, Kohgiluyeh and Boyer-Ahmad, and Zanjan had the lowest rates. During 2010-2021, the provinces of Golestan, Ardebil, Sistan and Baluchistan, West Azarbayejan, Kohgiluyeh and Boyer-Ahmad, and North Khorasan experienced the most increasing trend in BC burden, while Yazd and Semnan showed smaller increases or modest decreases. <i>Conclusions</i>: The rising FBC burden in Iran underscores the urgent need to strengthen cancer registries, expand screening programs, ensure equitable resource distribution, and implement targeted regional interventions focused on modifiable risk factors and early detection to reduce health disparities nationwide.