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. Last Updated: 07/27/2016

Breast Exams Little Help, Report Says

WASHINGTON -- A new, five-year study of female textile workers in China has found that regular breast self-examination did not reduce mortality from breast cancer nor produce earlier detection of tumors.


Although preliminary, the results tend to support the conclusions of a 1995 U.S. health task force that found insufficient evidence to recommend for or against teaching breast self-examination as a method to detect breast cancer.


"Our position is that we haven't really changed anything and that recommendation still holds,'' said David Thomas, epidemiologist and lead author of the study, who is at the Fred Hutchinson Cancer Research Center in Seattle.


Nevertheless, Thomas added that his study's findings, which appeared in last week's Journal of the National Cancer Institute, should not be taken to mean that breast self-examination is useless.


"I would not want the message to get out that women should not do breast self-examination. We wouldn't want to discourage that at all,'' especially with women at high risk of developing cancer, Thomas said. He said self-examination is an added precautionary measure that may help a woman detect sudden changes in her breasts, which could be a sign of disease.


The American Cancer Society estimates breast cancer strikes more than 184,000 people a year and is the second most deadly cancer for women, with 43,900 women projected to die of it this year.


Thomas said the new findings are most valuable as a guide for public-health officials deliberating how to use limited funds when launching public-awareness campaigns.


He suggested that, for example, public money might be better spent promoting regular mammograms for women over 50. There is widespread agreement among researchers that for women in this age bracket, regular mammograms help reduce breast-cancer deaths by about a third. Committing resources to promoting mammograms for these women vs. promoting breast self-examination would mean "you get more bang for your buck,'' Thomas said.


The new results follow a controversy in January, when a U.S. government-sponsored panel concluded that the scientific evidence on the benefits of mammograms for younger women -- in their 40s -- was not strong enough to justify a recommendation that these women have routine mammograms.


That mammography ruling and Thomas' new study raise questions about the benefits of long-standing recommendations from many cancer experts. In the new self-examination study, Thomas worked with Dao Li Gao, a public-health official specializing in cancer prevention in Shanghai. China had several advantages for a study on the benefits of breast self-examination.


First, "there was no routine mammographic screening,'' said Thomas. This meant that the researchers could more easily isolate the results of self-examination. "It might be difficult to detect an effect of breast self-examination if a lot of the women in the study were also getting mammograms,'' Thomas added.


The subjects of the study were 267,040 female workers. Between October 1989 and October 1991, 133,375 women were instructed in breast self-examination and a control group of 133,665 women were asked to attend classes on preventing back pain.


These Chinese women, who ranged from 31 to 64 years old when they entered the study, shared a similar diet and work environment and were easily monitored by researchers through medical clinics set up in the factories.


The women instructed in breast self-examination saw regular reminders to do the exam at their workplace. They were also asked to attend follow-up sessions. Researchers documented "a high level of participation'' by the women in the instruction sessions.


But in the follow-up, which continued through 1994, the researchers found 331 breast cancers in the group taught breast self-examination and 332 in the group schooled instead in back pain.


Also, "the breast cancers detected in the instruction group were not diagnosed at an appreciably earlier stage or smaller size than those in the control group,'' the study found.


Moreover, by the end of 1994, there was an equal number of deaths -- 25 -- from breast cancer in both groups. One big difference, however, was that the women doing self-examination detected more benign breast lumps (1,457) than women in the control group (623). This suggested that women trained in self-examination were more likely to notice changes in their breasts, researchers said.


For Thomas, it also "means that they are having more biopsies that did not turn out to be cancer. And if they are not accomplishing anything in terms of reducing mortality from breast cancer, then the biopsies are not warranted.''