The World Health Organization's (WHO) recent publication of global breast cancer survival estimates for women diagnosed between 2017 and 2021 has revealed stark disparities across regions. The global median five-year net survival rate was 77.8%, but this figure masks significant variations. Survival rates ranged from a concerning 39.1% in the African Region to impressive highs of 88.5% in the Region of the Americas and 84.0% in the European Region. This data highlights the profound impact of socioeconomic factors on breast cancer outcomes. In low-income countries, the median five-year survival rate was a grim 41.9%, while it rose to 60.1% in lower-middle-income countries, 78.7% in upper-middle-income countries, and a remarkable 87.3% in high-income countries.
These findings, published in Nature Medicine, serve as a crucial baseline for monitoring progress towards the WHO's ambitious Global Breast Cancer Initiative (GBCI) targets. The GBCI aims to reduce premature breast cancer mortality by 2.5% annually, ultimately saving 2.5 million lives by 2040. Breast cancer is a pervasive issue, being the most common cancer among women in 158 countries. In 2024, it claimed approximately 694,000 lives globally, with a staggering 70% of these deaths occurring in low- and middle-income nations. An estimated 8 million women worldwide are currently living with the disease, predominantly in high-income countries.
Dr Alarcos Cieza, Unit Head at WHO headquarters, emphasizes the significance of breast cancer survival as a barometer of a country's health system's effectiveness. It reflects the interplay of early detection, timely diagnosis, and access to effective treatment. This holistic approach empowers countries to assess their progress and pinpoint areas requiring improvement in their national breast cancer control efforts.
The analysis employed a sophisticated statistical model, integrating observed survival data from cancer registries in 67 out of 194 WHO Member States, along with critical covariates. These included stage at diagnosis, access to cancer medicines, radiotherapy capacity, mammography availability, and overall adult mortality rates. The study's findings underscore the critical role of early detection and treatment. Lower survival rates were observed in countries where breast cancer was diagnosed at more advanced stages, emphasizing the importance of the GBCI's operational pillars: diagnosing 60% of invasive breast cancers at stages I or II, achieving timely diagnoses within 60 days, and completing multimodality treatment for 80% or more of eligible patients.
The WHO's collaborative approach with Member States, involving a two-phase consultation process, ensured transparency and country ownership. This methodology allowed for the integration of observed national data while fostering a sense of shared responsibility for addressing the global breast cancer challenge.
