Methods of screening There is no evidence that clinical examination, breast ultrasonography, or teaching self examination of the breast are effective tools for early detection. However, randomised controlled trials have shown that screening by mammography can significantly reduce mortality from breast cancer by up to 40% in those who attend. The benefit is greatest in women aged 50-70 years. Published data from the combined Swedish trials showed an overall reduction in breast cancer mortality of 29% during 12 years of follow up in women aged over 50 who were invited for screening. View larger version: In this window In a new window Small carcinoma found on screening (arrow) Screening tests should be simple to apply, cheap, easy to perform, and easy and unambiguous to interpret and should identify those with disease and exclude those without. Film screen mammography requires high technology equipment, special film and dedicated processing, highly trained radiographers to perform the examinations, and highly trained readers to interpret the films. Mammography is at present the best screening tool available and was the first screening method for any malignancy which has been shown to be of value in randomised trials. The potential benefits of digital mammography remain to be evaluated. View larger version: In this window In a new window Summary of 7-12 years' mortality data from randomised and case-control(*) studies of breast cancer screening. Points and lines represent absolute change in mortality and confidence interval Key references Blamey RW, Day N, Young R, Duffy S, Pinder S . The UKCCCR trial of frequency of breast screening [abstract]. Breast 1999; 8: 215 Dupont WD . Risk factors for breast cancer in women with proliferative breast disease New Engl J Med 1985; 312: 146–51 Kertilowske K, Grady D, Rubins S, et al . Efficacy of screening mammography, a meta-analysis JAMA 1995; 273: 149–54 Nystrom L, Lutquist RLE, Wall S, et al . Breast cancer screening with mammography: overview of Swedish randomised trials Lancet 1993; 341: 973–8 Page DL . The clinical significance of mammary epithelial hyperplasia Breast 1992; 1: 3–7 Wald N, Murphy P, Major PE, et al . UKCCCR multi-centre randomised control trial of one and two view mammography in breast cancer screening BMJ 1995; 311: 1189–92