Abstract
BACKGROUND: Breast cancer is the most prevalent cancer among women and remains the leading cause of cancer-related deaths globally. While previous meta-analyses have explored predictors of breast cancer mortality, many have been limited by small sample sizes. This study seeks to fill this gap by synthesizing data from a larger pool of studies to comprehensively assess the relationship between breast cancer mortality and various risk factors, treatments, complications, and socio-demographic factors. By utilizing a large dataset, this review aims to provide a more robust understanding of the key determinants influencing breast cancer outcomes. METHOD: A thorough search was conducted up until June 2025 across multiple electronic databases, including Scopus, Medline, Web of Science (WOS), Cochrane Library, Google Scholar, and the Open Research Dataset Challenge. All human studies were included, regardless of language, publication date, or geographic location. A total of 70 studies, involving 2,447,155 patients, met the inclusion criteria. A random-effects model was used to pool the estimates. Sensitivity analysis and publication bias were also evaluated. RESULTS: The analysis revealed a pooled mortality rate of 16.89% (95% CI, 12.94-21.76%) among women with breast cancer. The Luminal B subtype was associated with increased mortality, while treatments such as lumpectomy with radiation and chemotherapy with trastuzumab showed a reduction in mortality risk. High allostatic load and advanced ECOG performance status were found to elevate mortality risk. Other risk factors included HIV positivity, positive lymph nodes, diabetes, large tumor size, older age, and obesity also correlated with higher mortality, while higher education levels appeared to reduce risk. Additionally, black race and current smoking were associated with increased mortality, whereas higher educational levels correlated with a lower mortality risk. CONCLUSION: In conclusion, this meta-analysis highlights key factors influencing breast cancer mortality, including treatment strategies, socio-demographic variables, and lifestyle behaviors. Our findings emphasize the need for targeted interventions and personalized care to improve survival outcomes and reduce global disparities in breast cancer mortality.