Radiation doses received in the UK Breast Screening Programme in 2001 and 2002.

Area of Science:

• Radiology
• Medical Physics
• Public Health

Background:

• Routine mammographic screening in the UK Breast Screening Programme (NHSBSP) involves regular measurement of mean glandular doses (MGD).
• Previous studies established baseline MGDs for mammography within the NHSBSP.

Purpose of the Study:

• To review a large dataset of MGD measurements from UK mammographic screening centres.
• To assess current radiation doses and compare them with previous findings and established reference levels.

Main Methods:

• Analysis of 53,218 mammograms from 16,505 women screened between 2001-2002, using 290 X-ray sets.
• Comparison of MGDs across different views, breast sizes, age groups, and X-ray equipment.

Main Results:

• Average MGD was 2.23 mGy (oblique) and 1.96 mGy (craniocaudal), similar to 1997-1998 levels.
• Advanced equipment reduced doses for large breasts; 97% of units were below the 2 mGy upper limit.
• Total dose per woman increased due to two-view screening, but the proposed NDRL of 3.5 mGy proved appropriate for identifying high-dose systems.

Conclusions:

• Mammography doses in the NHSBSP are generally well-controlled, with technological advancements benefiting patients with larger breasts.
• While overall dose per woman has risen with screening protocols, the established National Diagnostic Reference Level is effective.
• A revised definition of the 'standard breast' is needed to accurately reflect clinical practice and optimize dose monitoring.