Breast cancer is the most common malignancy among women worldwide, holding a significant position in both cancer-related incidence and mortality [1]. According to the World Health Organization (WHO), breast cancer accounted for approximately 670,000 female deaths in 2022, making it the leading cause of cancer-related mortality among women [2]. An estimated 2.3 million new cases of female breast cancer were diagnosed globally in 2020, representing 11.7 % of all new cancer cases, surpassing lung cancer as the most commonly diagnosed cancer [2]. As the global population continues to age, breast cancer incidence is expected to rise further, particularly in rapidly developing regions [3].

There are marked disparities in breast cancer incidence across different geographical and socioeconomic groups [4]. These geographic differences are influenced by various factors, including environmental conditions, lifestyle choices, and access to healthcare services [5]. The Human Development Index (HDI) is a composite index that measures a country's average achievement in health, education, and income, and ranges from 0 to 1 [6]. Based on standard thresholds (0.5, 0.7, 0.8), countries are divided into four categories: low, medium, high, and very high HDI. The WHO reported that the burden of female breast cancer was higher in countries with a high HDI in 2022, with approximately one in every 12 women being diagnosed with the disease [7]. For instance, there were more than 80 cases of incidence in breast cancer per 100,000 women in Western Europe in 2020, with a mortality of 6.4 % [8]. In contrast, in low HDI countries, the incidence was lower in 2022, with about one case for every 27 women, but mortality rates remained high, at approximately 1 in 48 women [7]. For instance, although the cases of incidence were below 40 per 100,000 women in some regions of Africa, the proportion of breast cancer deaths in Africa was much higher (accounting for 12.5 % of global deaths) [8]. Space-time patterns are regular, repetitive, or significant data distribution or dynamic characteristics in the dimensions of time and space, and the analysis of these space-time patterns is essential to guide effective prevention, control, and resource allocation strategies [9]. Previous studies have predominantly focused on temporal trends without adequately integrating spatial distributions. While some studies have investigated clustering and directional trends, most research has concentrated on specific regions, often overlooking the broader global perspective necessary to address regional disparities in the burden and distribution of breast cancer [10], [11].

The lack of integration between temporal, spatial, and space-time analyses in previous studies necessitated a comprehensive approach to better understand the global dynamics of female breast cancer. Addressing these gaps, the study employed an integrated framework to analyze the temporal trends, spatial distribution, and space-time variations in disease burden of female breast cancer of all age groups in 204 countries from 1990 to 2021. Specifically, the objectives were to: (1) explore the long-term trends in global female breast cancer incidence and mortality; (2) analyze spatial expansion processes and directional tendencies, identifying clustering patterns and geographical characteristics; and (3) investigate dynamic variation trends in female breast cancer across temporal and spatial dimensions, pinpointing high-risk regions over distinct timeframes. By offering a global perspective, this research provides valuable insights to guide targeted interventions, optimize health resource allocation, and inform policies to address regional disparities in prevention, screening, and care.