Study recasts value of breast self-exams

By Paul Recer
Associated Press

WASHINGTON — Women examining their breasts are unable to detect tumors early enough to reduce their risk of dying from breast cancer, suggests a decade-long study of more than 260,000 women in Shanghai.

Dr. David Thomas, lead author of the study, said women should not stop examining their breasts but should have realistic expectations about the value of the exams.

"She's got to do a very good job, and she's got to realize it is unproven," Thomas said. He said self-examination should not be a substitute for mammography.

The finding was the latest in the confusing, often contradictory information women have been given over the past year relating to breast cancer and early detection. A study earlier this year questioned the value of mammograms in detecting cancers and saving lives.

Thomas said the latest study, appearing today in the Journal of the National Cancer Institute, raises questions about the time and expense it takes to teach breast self-examination to women, especially those in developing countries.

His conclusion is based on a decade-long effort to teach factory workers in Shanghai, China, the proper way of doing breast self-examination and to determine if the effort made a difference in the rate of cancer deaths.

"In spite of the fact that we spend all of this time and effort in teaching breast self-exam, the women were not able to detect lumps early enough to make a difference," Thomas said.

In poorer countries, where mammography is not routinely available, Thomas said the study suggests that public health officials should not spend their limited money on teaching self-examination but on other programs, such as immunizations.

In the United States, where mammography is common, doctors should not emphasize breast self-examination, he said.

"Unless a woman is highly self-motivated, I wouldn't push it on her because it may be a waste of time," Thomas said.

Other experts, however, said the study will not affect their continuing recommendation that women perform self-examinations between their regular routine breast screening tests.

"It remains important for women to be familiar with their own anatomy, and certainly teaching signs and symptoms of cancer is of value," said Dr. Benjamin Anderson, a breast surgeon and the clinical medical director of the Breast Care and Cancer Research Program at the University of Washington. "We will continue to recommend monthly self-examination as part of routine breast healthcare. We will not be abandoning that aspect."

Anderson said many instances occur in which self-examination by women picked up cancers and "got the process (of treatment) started."

Dr. Kimberly Van Zee, breast cancer surgeon at the Memorial Sloan-Kettering Cancer Center in New York, said the study did not determine self-examination to be of no value, but teaching the procedure as a broad public health measure may not be useful in countries where mammography and other breast cancer screening exams are not available.

"Among motivated women who do regular breast self-exam and are very proficient at doing it, it might make a difference, but this study did not test that," Van Zee said.

"My approach is not to discourage a patient from doing breast self-exam," she said. But she said a woman needs to be told it "is not the be-all and end-all. She needs to have other screening done on a regular basis."

An editorial in the cancer journal by Drs. Russell Harris and Linda Kinsinger of the department of medicine at the University of North Carolina at Chapel Hill said the study "should lead us to change our clinical practice."

American physicians, the editorial said, "can stop spending time routinely teaching women's fingers" to do self-examination and, instead, concentrate more on clinical examinations for breast cancer.

Thomas said that, in theory, self-examination should find small breast cancer lumps at a point when they could be treated easily and eliminate the cancer threat. Despite a major effort to teach the Shanghai women and to monitor their self-examinations, the researchers found as high a level of cancer deaths among patients trained in self-examination as among those who did not receive the training.

In the study, researchers randomly assigned half of about 266,000 women factory workers in Shanghai to one of two groups. Women in one group were all trained to perform the examinations properly. They received monthly reminders, then conducted the exams under medical supervision every six months for five years. The second group of women received no information on breast cancer screening.

Thomas said that after more than a decade, the researchers found almost no difference between the two groups in the rate of death from breast cancer. Among those in the instruction group, 135 women died of breast cancer. Among women in the other group, 131 did.

Women who examined their breasts found more benign lumps that required medical attention, said Thomas, but there was no reduction in the rate of breast cancer.

Despite the study, Thomas conceded that "highly motivated women" could benefit from self-examination practiced between regular breast cancer screenings. But he said such patients should be aware that the survival benefit of the procedure is unproven, and the technique does increase the chances of having a breast biopsy that does not find cancer.