Detection rates for breast cancer risingBMJ 2000; 321 doi: https://doi.org/10.1136/bmj.321.7269.1101/b (Published 04 November 2000) Cite this as: BMJ 2000;321:1101
The performance of the United Kingdom's breast cancer screening programme is improving, with its sensitivity and specificity increasing at the same time.
Figures from its annual report show that the scheme is detecting more cancers, and more smaller cancers (less than 15 mm diameter), while doing fewer unnecessary biopsies. The take up rate from women invited for screening has also improved, with more than three quarters of the 1.7 million women invited taking up the offer.
The improved performance is attributed to increased skills among staff; changes in film density that help to give a sharper, better quality image; and the introduction of two view mammography for women attending for the first time.
A recent study, published in the BMJ (16 September, p 665-9), estimated that the reduction in mortality directly attributable to screening (as opposed to improved treatment) by 1998 in England and Wales was 6.4
Mortality from screening is not falling as fast as was predicted in the Forrest report, however. That report, published in 1987, predicted a 25% mortality reduction by the year 2000.
Dr Roger Blanks from the cancer screening evaluation unit at the Institute of Cancer Research and one of the authors of the study published in the BMJ, explained why the fall was not as rapid as originally expected.
“The speed at which you expect to see an effect on national statistics is much slower that you would expect to see in randomised controlled trials, because of the dilution of the effect by women with prediagnosed cancer,” he said.
Moreover, screening did not cover the whole of the United Kingdom until 1995, and it took time to build up UK national expertise in screening.
The number of women aged 65 and over who were screened rose again in 1998-9, partly because of the pilot schemes being run for women of that age and also because of an increasing awareness of screening among older women.
The annual review is available in the Recent News section of www.cancerscreening.nhs.uk