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| Breast Self-Exam: Current Research and Recommendations |
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Updated July 2008 Position What is Breast Self-Exam (BSE)? Women frequently touch their own breasts while showering, dressing, having sex, etc. Some doctors urge women to touch their breasts often so that they know what their breasts normally feel like and can identify when unusual changes occur. However, BSE is different than simply touching your breasts and "getting to know" your breasts. It is a method developed for the specific purpose of searching for cancer. Some people feel that this deliberate searching makes women overly anxious about breast cancer and unnecessarily fearful about every lump that they find. In some cases, this fear may eventually discourage women from touching their breasts. About 80% of breast cancers not discovered by mammography are discovered by women themselves.3 Some women find cancer during a breast self-exam; however, many women find cancer when they are touching or observing their breasts for other reasons. Breast cancer is also occasionally discovered when a woman's spouse or lover feels a lump inside her breast. In one study, only 7.6% of breast cancer patients who had practiced BSE on a regular basis actually found their breast cancers while performing BSE.4 Thus, it is unclear whether BSE aids women in discovering breast cancer. BSE as a Public Health Intervention People began to promote and teach BSE long before it had been adequately studied and long before we knew if it worked. For the past few decades, many organizations have strongly recommended that every woman age 20 and older perform BSE each month. Many of these same organizations have spent considerable resources on shower cards, educational programs, videos, etc. that instruct women to use proper BSE technique.5 Some companies have even begun to produce and sell models of the breast for the purpose of teaching women how to perform BSE. In addition, many physicians and nurses spend time promoting BSE and teaching the technique to their patients.6, 7 Due to these efforts, women have come to believe that BSE is a life-saving intervention, even though there is no evidence showing this to be true. Several questions about BSE must be answered before we begin to advocate for BSE on a population-wide level. Does promoting and teaching a monthly regimen of BSE really help women catch breast cancers earlier than they would without the instruction? More importantly, does discovering these breast cancers actually result in lives saved? And finally, does this type of intervention have any risks or negative consequences? These are difficult questions that can only be answered by conducting scientific studies. Thus far, scientific studies have not shown that the benefits of BSE outweigh the risks. Research on BSE Two randomized clinical trials of BSE have been conducted -- one in St. Petersburg, Russia13 and one in Shanghai, China.14 In both of these trials, women who were taught BSE had the same breast cancer mortality (death) rate as women who were not taught BSE. Moreover, the stages of the breast cancers detected in each group of women were similar. Thus, BSE instruction did not result in earlier detection of breast cancer, and it did not save or extend the lives of women. A systematic review that analyzed the Russian and the Chinese trials together found no beneficial effect of BSE screening on deaths from breast cancer. On the downside the analysis showed that twice as many biopsies with benign results were performed in the screened groups compared to the control groups.15 To learn more about the observational studies and clinical trials of BSE, See NBCCF's Analysis of BSE Research. Recommendations We cannot afford to waste our limited resources on a public health intervention that has not been shown effective, particularly when there is evidence that the intervention may be causing harm. These resources would be better spent on funding more research studies to identify interventions that really work, such as better ways to detect, treat, and prevent breast cancer. These resources would also be better spent on interventions that have already been shown to reduce breast cancer mortality, such as providing appropriate treatment for all women diagnosed with breast cancer. Conclusion In addition to NBCC, several other national health organizations have stated that there is insufficient scientific evidence to conclude that BSE benefits women. The National Cancer Institute (NCI) no longer prints a BSE guide in its breast cancer booklet, "Understanding Breast Changes." The U.S. Preventive Services Task Force states that "the evidence is insufficient to recommend for or against teaching or performing routine breast self-examination.16 In addition, the American Cancer Society is phasing out materials that focus only on breast self-exam. Currently, there are no highly effective screening tools for women in any age group. Two published systematic reviews have cited methodological problems in the original clinical trials of mammography.17, 18 Thus, the evidence for mammography screening is unclear, and the decision to undergo screening must be made on an individual level. For more information on mammography screening, see NBCCF's fact sheet entitled, The Mammography Screening Controversy: Questions and Answers. It is very unfortunate that, at this point, women have no adequate breast cancer screening options. But NBCC is hopeful that this knowledge will encourage more women to fight for the research needed to develop better screening tools, preventions and treatments for breast cancer. About NBCCF Breast Self-Exam (BSE) Research: NBCCF's Analysis Several cross-sectional, case-control, and cohort studies, and a systematic review, have examined the effects of BSE in a population of women. In these observational studies, researchers observed women who chose to practice BSE and examined whether these women detected earlier stages of breast cancer and/or survived longer than women who did not choose to practice BSE. These studies have had conflicting results, but most have failed to show that BSE benefits women. Unfortunately, the results of these studies may be unreliable because observational studies have several limitations when they are used to examine a screening technique such as BSE.19 For example, there may be several differences between women who choose to practice BSE and women who do not choose to practice BSE that could bias the results of the study. Breast cancer screening techniques must be examined in the context of randomized clinical trials in order to determine if they are effective. There have been two randomized clinical trials of BSE. In each of these trials, researchers invited a large number of women to participate, and then randomly assigned these women to one of two groups. One group of women received thorough instruction in BSE and the other group, the control group, did not receive this instruction. Both groups were followed for a number of years. At the end of the follow-up period, the researchers compared the groups to determine if there were any differences in the number of women who were diagnosed with breast cancer or who died of breast cancer (mortality rate). The first trial, which was conducted in St. Petersburg, Russia, followed 122,471 women between the ages of 40 and 64. Trained nurses and physicians demonstrated how to perform BSE to women in the BSE group. Unfortunately, many women in the BSE group did not actually practice BSE after they were taught the technique; by the fifth year of follow-up, only 55.8% of the women practiced BSE at least 5 times per year. After 9 years of follow-up, the group that was taught BSE and the group that was not taught BSE had the same breast cancer mortality rate. There was also no difference in the stage of breast cancers diagnosed. However, BSE did result in a higher rate of biopsies for benign lumps. The best-designed study of BSE was a randomized trial of 267,040 women ages 31-64 conducted in Shanghai, China. Women received individual instruction in BSE using silicone breast models and they were given many reminders to practice the technique. Most women in the BSE group practiced BSE during the study period, and they were very competent in performing the technique. After about 10 years of follow-up, the group that was taught BSE and the group that was not taught BSE had the same breast cancer mortality rate. There was also little evidence that BSE enabled women to find their cancers earlier. The BSE group and the control group found the same number of cancers each year of the study. In addition, the number of cancers that had spread to the lymph nodes was similar in each group. However, the BSE group detected many more benign lumps than the control group did. A systematic review that analyzed the Russian and the Chinese trials together – greatly expanding the statistical power - found no evidence for beneficial effects pf BSE on breast cancer. The review did, however, confirm that there twice as many biopsies with benign results in the screened groups compared to the control groups. The review also considered a trial looking at the benefit of clinical physical breast exam, but that trial was discontinued prematurely and did not accrue adequate data to answer the question.15 In summary, most studies have not demonstrated a benefit of BSE in women. Results from several studies, including the two randomized trials, show that BSE screening greatly increases the number of benign lumps detected. This negative consequence of BSE results in increased anxiety, physician visits, and unnecessary biopsies. Although breast biopsies are relatively simple surgeries, they use scarce health care resources and can cause distress, scarring and disfigurement. Recently, the Canadian Task Force on Preventive Health Care issued recommendations on BSE after reviewing the observational studies and clinical trials discussed above.20 The conclusion of the Task Force was that there is no evidence that teaching BSE to any age group reduces breast cancer mortality.
1 Love S, Lindsey K. Dr. Susan Love's Breast Book, 2nd ed. Reading, MA:Addison-Wesley, 1995;25. |



