Regional variation in breast cancer survival in Finland

Abstract Background: Breast cancer survival in Finland is among the highest globally, with ten-year relative survival approaching 90% (or 5-year survival over 90%). Given the country’s universal healthcare system, this study aimed to describe the variation in five- and ten-year relative survival from breast cancer in Finland to identify potential regional disparities in outcomes. Materials and Methods: We performed a nationwide registry-based cohort study by using Finnish Cancer Registry (FCR) data for all female breast cancers diagnosed in 2000–2022. 5 and 10-year survival were compared across 23 welfare regions by estimating age-standardised Relative survival (RS) for each region. Results: Five-year RS improved from 88% in 2000–2004 to 92% by 2015–2019, and ten-year RS rose from 82% in 2000-2004 to 87% in 2010-2014. The overall median age at diagnosis was 63.4 years. In each period, a few regions had slightly lower or higher survival than the national average, but differences were small (