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06:42
Optimization of Breast Biopsy and Mastectomy Sample Collection Procedures for Biobanking, Personalized Medicine, and Research Applications
Published on: September 2, 2025
The evidence base for breast cancer screening
Paul Glasziou1, Nehmat Houssami
1Centre for Research in Evidence-Based Practice, Bond University, Gold Coast, 4229 Australia. pglaszio@bond.edu.au
Preventive Medicine
|June 11, 2011
Summary
Breast cancer screening shows a 19% reduction in mortality. However, this translates to less than 1% of all-cause mortality reduction, with benefits and harms needing careful consideration.
Area of Science:
- Oncology
- Public Health
- Epidemiology
Background:
- Breast cancer screening has a long history marked by controversy and varying study designs.
- Decades of research provide substantial evidence on screening effectiveness.
Purpose of the Study:
- To analyze the overall effectiveness of breast cancer screening based on combined trial data.
- To evaluate the impact of screening on mortality and consider modern treatment advancements.
Main Methods:
- Combined analysis of intention-to-treat results from 10 trials spanning 4 decades.
- Modeling to assess the impact of improved systemic therapies on survival rates in screened and non-screened groups.
Main Results:
- A 19% relative reduction in breast cancer mortality observed in intention-to-treat analyses.
- An approximate 25% relative reduction for attendees, translating to <1% reduction in all-cause mortality.
- Modern treatments may reduce the absolute risk reduction difference from screening.
Conclusions:
- Breast cancer screening offers a significant relative mortality reduction but a small absolute reduction in all-cause mortality.
- Balancing screening benefits against harms like over-diagnosis is crucial, varying by age group.
- Incorporating patient perspectives is vital for future breast cancer screening policy development.
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