No randomized trials of clinical breast examination (CBE) as a sole screening modality have yet been reported. The Canadian National Breast Screening Study (NBSS) compared high-quality CBE plus mammography to CBE alone in women aged 50 to 59 years (refer to the Clinical Breast Examination section in the Overview section of this summary for more information). CBE, lasting 5 to 10 minutes per breast, was conducted by trained health professionals, with periodic evaluations of performance quality. The frequency of cancer diagnosis, stage, interval cancers, and breast cancer mortality were similar in the two groups and compared favorably with other trials of mammography alone, perhaps because of the careful training and supervision of the health professionals performing CBE. Breast cancer mortality with follow-up 11 to 16 years after entry (mean = 13 years) was similar in the two screening arms (mortality rate ratio, 1.02 [95% confidence interval [CI], 0.78–1.33]). The investigators estimated the operating characteristics for CBE alone; for 19,965 women aged 50 to 59 years, sensitivity was 83%, 71%, 57%, 83%, and 77% for years 1, 2, 3, 4, and 5 of the trial, respectively; specificity ranged between 88% and 96%. Positive predictive value (PPV), which is the proportion of cancers detected per abnormal examination, was estimated to be 3% to 4%. For 25,620 women aged 40 to 49 years who were examined only at entry, the estimated sensitivity was 71%, specificity was 84%, and PPV was 1.5%.
The U.S. Preventive Services Task Force (USPSTF) is recommending sweeping
changes in its breast
cancer screening guidelines.
The USPSTF, which is a group of independent health experts convened by the
Department of Health and Human Services, reviewed and commissioned research to
develop computer-simulated models comparing the expected outcomes under
different screening scenarios.
Here are the USPSTF's recommendations, based on all that work:
Routine screening of average-risk women should...
Among community clinicians, screening CBE has higher specificity (97%–99%)  and lower sensitivity (22%–36%) compared with examiners in clinical trials of breast cancer screening.[5,6,7,8] A study of screening in women with a positive family history of breast cancer showed that, after a normal initial evaluation, the patient herself or her clinician performing a CBE identified more cancers than did mammography. Another study examined the usefulness of adding CBE to screening mammography; among 61,688 women older than 40 years and screened by mammography and CBE, sensitivity for mammography was 78%, and combined mammography-CBE sensitivity was 82%. Specificity was lower for women undergoing both screening modalities than it was for women undergoing mammography alone (97% vs. 99%). Two international trials of CBE are under way in India and Egypt.
Monthly breast self-examination (BSE) has been promoted, but there is no solid evidence that it is effective in reducing breast cancer mortality.[11,12] The only large, well-conducted, randomized clinical trial of BSE randomly assigned 266,064 women factory workers in Shanghai to receive either BSE instruction with reinforcement and encouragement, or instruction on the prevention of lower back pain. Neither group received any other breast cancer screening. After 10 to 11 years of follow-up, 135 breast cancer deaths occurred in the instruction group, and 131 cancer deaths occurred in the control group (relative risk [RR] = 1.04; 95% CI, 0.82–1.33). Although the number of invasive breast cancers diagnosed in the two groups was about the same, women in the instruction group had more breast biopsies and more benign lesions diagnosed than did women in the control group.