In recent years, increasing numbers of women with breast cancer in one breast have been choosing to have the other breast removed as a precaution – prophylactic or preventive mastectomy. But a new study finds a survival benefit of less than 1 percent over 20 years for women who’ve had a preventive mastectomy.
Dr. Todd Tuttle, one of the researchers, said, “We found fairly convincing evidence that there really is no meaningful long-term survival benefit for the vast majority of women with breast cancer by having their opposite breast removed,” the news service HealthDay reports. Tuttle is chief of surgical oncology at the University of Minnesota School of Medicine. “Most patients have very minimal increases in life expectancy, one to seven months,” Tuttle said. And that difference was spread over two or more decades, especially in the younger women.
Younger women with stage I, estrogen receptor-negative breast cancer (the type not fueled by estrogen) had the greatest survival benefits from the procedure, according to HealthDay. But the survival difference was still less than 1 percent over 20 years, according to the study, published July 16 in JNCI: Journal of the National Cancer Institute.
None of the women in this study had the BRCA-1 and BRCA-2 genes, which significantly increase a woman’s risk of breast and ovarian cancer, according to the National Cancer Institute. Women with a BRCA gene often choose preventive surgery to remove breasts and ovaries because of their increased risk, HealthDay reports.
Tuttle’s team tracked survival over 20 years for more than 100,000 women with stage I or stage II breast cancers. The researchers then used a model to simulate survival results in women who had prophylactic mastectomy and those who did not. According to the researchers, unfounded fears prompt some women to have their healthy breast removed. One study found that 94 percent of women 40 and under who chose preventive mastectomy did so to boost their survival rate, although only 18 percent thought the procedure would actually do that, according to HealthDay. Tuttle said the procedure gives “a false sense of security.”
Women who have had breast cancer in one breast are at increased risk of developing cancer in the opposite breast, Tuttle said, but the chance is about 4 or 5 percent over the next 10 years, according to the medical literature. Overall survival depends on “whether the original cancer spread, not whether you get a new one,” HealthDay reports.