Breast cancer was estimated to be the most commonly diagnosed cancer and the leading cause of cancer death among females in Europe in 2022, with about 470,000 new cases and 120,000 deaths. Mammography screening programmes have been widely implemented across European countries over the past 40 years with the aim of detecting breast cancer earlier and reducing mortality. Screening strategies have varied considerably between countries, particularly in timing of introduction, coverage and uptake, and in some settings organised population-based programmes have not been implemented or only pilot activity has been available. Over the same period, improvements in quality of care, diagnostics and treatment have also shaped outcomes.
Long-Term Incidence and Mortality Trends Across 21 Countries
The analysis covered 1978–2019 and included 3,420,902 female cases of invasive breast cancer and 211,804 cases of in situ breast cancer. Incidence data were obtained from population-based cancer registries, while mortality data and population denominators were provided by national statistical offices and cancer registries. Denmark, Finland and Iceland contributed aggregated incidence and mortality series from NORDCAN. Annual age-standardised rates were calculated using the 1976 European Standard Population.
Across four decades, age-standardised breast cancer incidence increased, and age-standardised breast cancer mortality decreased in the large majority of included countries and regions. Incidence increases were strongest in 1978–1987 and 1988–1997, while mortality decreases were most predominantly observed in 1998–2007 and 2008–2018/19. When trends were examined in relation to screening implementation, incidence in the 10 years before screening introduction generally increased or remained stable where estimates were available. In the decade after programme introduction, incidence typically increased or stabilised, with significant declines reported only in Austria and the Flemish region of Belgium. In some settings, including Denmark, Germany and the Netherlands, incidence rose sharply after programme introduction before declining in subsequent years. In contrast, Bulgaria and Ukraine, where organised screening was not in place or limited to pilot activity, showed a steady increase in age-standardised incidence over time.
Earlier Stage Detection and Advanced Disease Patterns
The largest incidence shifts were reported for in situ disease, stage I cancer and stage IV cancer. After screening implementation, substantial increases in incidence of in situ and stage I disease were observed in countries with programmes introduced before 1998 where stage data were available, and in most countries with later implementation. These changes were particularly pronounced among women in the screening target age group, mostly 50–69 years.
At the advanced end of the spectrum, incidence of stage IV cancer declined or remained stable in most countries after screening introduction. Statistically significant declines in stage IV incidence were reported for Norway, South Portugal, the Flemish region of Belgium, the Czech Republic, Germany and Lithuania, with average annual percent changes (AAPCs) ranging from −6.16 (95% confidence interval, CI −8.28 to −4.00) to −2.04 (−2.82 to −1.25). Significant increases in stage IV incidence were reported for Doubs in France and for Ireland. In Bulgaria and Ukraine, incidence of stage I cancer increased, while stage IV incidence decreased over time in Bulgaria and remained relatively stable in Ukraine.
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The discussion also addressed overdiagnosis, defined as detection of cancers that would not have been diagnosed or caused death during a person’s lifetime. European studies accounting for lead time and contemporaneous incidence trends were described as estimating overdiagnosis at 1–25% of detected cases.
Age-Specific Trends and Programme Timing Differences
Age at diagnosis shaped incidence and mortality patterns. In situ and stage I incidence increased across age groups in most countries but was overall most pronounced among women targeted by screening and, for several countries, among older age groups. Stage II incidence was described as decreasing substantially in the years after screening implementation among women in the screening age group in most countries, although trends varied between countries. Larger decreases were reported for stage III and stage IV incidence, particularly among women aged 50 years and older.
Some increases in early-stage incidence began before organised programme rollout. Austria and the Czech Republic were described as settings where earlier increases likely reflected widespread opportunistic screening before programme introduction. Patterns among women aged 0–49 years were discussed in relation to access to care and mammography use for opportunistic screening or diagnostic purposes. Survey data from 2013–2015 indicated that, in several countries including Austria, Bulgaria, France, Portugal and Sweden, over 30% of women under 50 had undergone a mammogram within the preceding two years.
Breast cancer mortality declined considerably especially among women aged 0–49 years and 50–69 years, whereas no significant changes or even increasing rates were reported for women aged 80 years and older in most countries. Mortality declines after screening initiation reached up to about 3% annually in some settings, with the lowest reported post-initiation AAPC estimate of −3.29 (95% CI −6.26 to −0.23). Declines before screening introduction were also observed in countries where organised programmes were implemented later, while mortality declines were described as minimal or absent in Bulgaria and Ukraine.
Across 21 European countries between 1978 and 2019, breast cancer incidence increased while mortality decreased in most settings, with incidence rising most strongly in earlier decades and mortality reductions emerging most clearly from the late 1990s onwards. After programme implementation, detection shifted towards in situ and stage I disease, while stage IV incidence declined or remained stable in most countries, particularly among screening-target age groups. Mortality declines aligned with these patterns, alongside advances in diagnostics and treatment, while substantial differences between countries and age groups underscored the importance of local screening context, programme roll out and broader cancer control progress.
Source: The Lancet Regional Health – Europe
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