Women who have genetic mutations giving them a high risk of breast cancer can virtually eliminate the risk by having their breasts removed, researchers reported on Monday.
The women who opted for double mastectomies reduced their breast cancer risk by 90 percent, the international team of researchers reported.
They did not check to see if the women’s death rate from breast cancer was also reduced -- breast cancer is curable --but said they assumed this would be the case.
“Our study shows that bilateral prophylactic mastectomy markedly reduces the risk of breast cancer in women who are genetically predisposed to the disease,” said Dr. Barbara Weber, a professor of medicine and genetics at the University of Pennsylvania, who led the study.
“Women undergoing this procedure should feel confident that if they choose this risk management option, it will reduce their risk of breast cancer to almost zero.”
The women in the study had mutations in genes called BRCA1 and BRCA2, which greatly increase the risk of breast cancer. Some such women have opted to have mastectomies instead of living with the fear of breast cancer.
Writing in the Journal of Clinical Oncology, Weber and her colleagues said they followed 483 women from 11 sites in the United States, Canada, United Kingdom and the Netherlands over six years. All of the women had BRCA mutations and some opted for the mastectomies.
Breast cancer, which can develop in lymph nodes outside the breasts, was diagnosed in two of the 105 women who had mastectomies, or 1.9 percent. But 184 of the 378 women who did not undergo the procedure developed breast cancer -- or 48 percent.
Weber said mastectomy should be up to the woman, but she strongly recommended that women with BRCA1 and BRCA2 mutations should have their ovaries removed after they finish having children.
BRCA mutations also raise the risk of ovarian cancer, a rare but deadly cancer. Unlike breast cancer, it cannot be detected in early stages.
But having the ovaries removed brings on early menopause. The symptoms of menopause can be treated with hormone replacement therapy, but in women with their ovaries such therapy raises the risk of heart disease, stroke and some cancers.
Weber’s team said the overall life expectancy of women who had their ovaries taken out did not change.
