Collecting high-quality data for advanced breast cancer: a global expert review and call-to-action for 2025-2035...

The systematic collection and analysis of high-quality advanced breast cancer (ABC) data is necessary to advance understanding, optimize care, and improve patient outcomes. High-quality data enables understanding of treatment effectiveness, thereby facilitating the development of innovative therapies. ABC data may also help to counter stigma, by demonstrating that many living with the disease continue to contribute meaningfully to society. Data is an essential tool in highlighting global inequities and advocating to overcome them, and prevalence data is key to determining the burden of ABC worldwide, informing healthcare policies and investment in ABC care. This manuscript reviews global efforts to improve the collection and analysis of ABC data over the past decade. It highlights the advances and persistent challenges to high-quality data collection and proposes actions for the decade ahead. It summarizes research conducted for the ABC Global Alliance's Global Decade Report 2.0. The main findings are: a) New methodologies yield more accurate estimates of the number of people with ABC; b) Data linkage initiatives reveal ABC prevalence far higher than earlier projections; c) ABC-focused registries have advanced data collection globally over the decade; d) High-quality ABC data has been shown to drive treatment access and policy change; e) Persistent gaps in recurrence data and registries remain. The findings from the ABC Global Alliance's Global Decade Report 2.0 have informed the development of a new ABC Global Charter. The ABC Global Charter 2.0 defines ten new achievable and measurable goals for the decade 2025-2035, aiming at improving the lives of people living with ABC worldwide.