Screening mammography--early detection or over-diagnosis? Contribution from Australian data

Area of Science:

• Oncology
• Public Health
• Radiology

Background:

• Organized mammography screening programs aim to reduce breast cancer mortality.
• The effectiveness of screening mammography is debated, particularly in populations with early disease detection and access to adjuvant treatments.

Purpose of the Study:

• To critically evaluate the benefits and harms of organized screening mammography.
• To analyze the impact of screening mammography on breast cancer mortality and over-diagnosis, referencing Australian data.

Main Methods:

• Systematic review of published literature.
• Analysis of breast cancer-specific mortality trends.
• Assessment of adjuvant treatment effectiveness and impact on non-breast cancer mortality.
• Evaluation of over-diagnosis magnitude.

Main Results:

• Reductions in breast cancer mortality are primarily attributed to adjuvant therapies, not screening mammography.
• The impact of screening mammography is modest in settings with early diagnosis and effective adjuvant treatments.
• Over-diagnosis is a significant issue, with estimates varying widely. All-cause mortality is a more appropriate metric for assessing screening impact.

Conclusions:

• The benefits and harms of screening mammography are closely balanced, with potential for overall harm.
• Informed consent regarding over-diagnosis is crucial for women.
• A review of the continuation of organized mammographic screening programs is warranted.