Breast cancer screening: From science to recommendation

We greatly appreciate the invitation from the editor of Radiology to provide a brief description of the USPSTF and the methods and procedures used to develop our recent recommendations on breast cancer screening; a focused overview of the recommendations, including clarification of aspects of the recommendations that have been misinterpreted by some; and the opportunity to address a number of incorrect statements made by critics of the recommendations. Neither of two RCTs found benefits of physicians teaching breast self-examination to women. There is insufficient evidence to demonstrate an incremental benefit of breast self-examination by women who undergo annual or biennial screening mammography. However, abnormal findings detected at breast self-examination warrant clinical evaluation and follow-up. Our comprehensive systematic review of RCTs confirms the net benefits and underscores the strong recommendation for routine screening mammography in women between the ages of 50 and 70 years. Furthermore, rigorous decision model analyses of breast cancer screening and natural history provide moderate evidence of the benefits of extending routine mammographic screening to women aged 70-74 years. However, evidence from the BCSC and the decision models indicate that most of the benefits of annual screening mammography can be attained through biennial screening, while dramatically reducing harms associated with mammographic screening. Similarly, the results of the AGE trial that was designed to assess the net benefit of screening mammography in women aged 40-49 years and the systematic review, the meta-analysis of previous RCTs (including those with extended follow-up), and the breast cancer screening models all demonstrate a small net benefit of screening mammography among women aged 40-49 years. Thus, screening among women in this age range is best addressed by individualized decision making between a woman and her primary care physician, incorporating the woman's preferences and values. There is insufficient evidence to make any informed recommendation regarding screening mammography in women 75 years or older or regarding superior net population benefit of digital mammography or screening with breast magnetic resonance imaging. Breast cancer remains a major source of morbidity and mortality in the United States, affecting approximately one (12.5%) in eight women who live to the age of 90 years. Screening mammography leads to earlier detection and reduced mortality in women aged 40-74 years, with the magnitude of the benefit small for women aged 40-49 years and greatest for women aged 50-74 years. Further progress in reducing breast cancer morbidity and mortality will require a better understanding of methods for primary prevention, more effective therapy, and improved diagnostic tests that reduce false-positive results and identify women with lesions likely to benefit from therapeutic intervention.