Produced by the Royal College of Physicians of Edinburgh and Royal College of Physicians and Surgeons of Glasgow

Screening for breast cancer

  • Ms EDC Anderson, Consultant Surgeon, Edinburgh Breast Unit and Clinical Director of Southeast Scotland Breast Screening Centre, Edinburgh, Scotland

Summary

There is a battlefield of scientific literature debating the value of breast screening. How effective is breast screening and who should be screened? Ms Elaine Anderson provides a review of the evidence and the outcomes of the NHS breast screening programme in the UK.

Key Points

  • Breast screening in women aged 50 years and over reduces mortality from breast cancer by about 35%. This equates to two women in every 1000 screened in the UK.
  • Cancer detection rates in “high-risk” women aged under 50 years are the same as in those aged 50 years and older, but the effects of this on breast cancer mortality is not known.
  • The risk of breast cancer increases with age, and women should not reject screening as unnecessary on grounds of age alone. The age range for screening by invitation in Scotland was extended to 70 years in 2003/04.
  • Mammography is not invasive, and the radiation dose involved is low.

Declaration of interests: No conflict of interests declared

In 1986, the Forrest Report recommended that breast screening should be introduced for all women between the ages of 50 and 64 in the UK.1 Whilst women over the age of 64 were also to be eligible for screening, it was decided that these women should initiate their own invitations for screening due to poor compliance in Swedish studies of women in this age group.2 The method of screening to be used was to be a single oblique mammogram at an interval of three years. Subsequent research has shown that 2-view mammography at the time of first screen can improve sensitivity, i.e. number of cancers detected (24%), and reduce the number of benign recalls by 15%.3

There is now a battlefield of literature debating the value of breast screening. Review of currently published data on the effect of breast screening, including the large randomised trials (Swedish Two Counties and the Health Insurance Plan (HIP) project) suggests that a reduction in breast cancer deaths in the order of 21-35% at five years should be expected for women over the age of 50.2,4,5,6,7,8 The robustness of the evidence confirming the value of breast screening in reducing breast cancer deaths was confirmed by the International Agency for Research on Cancer (IARC), who convened an international pa