Prophylactic surgery to remove the breasts and ovaries is an effective way to reduce the risk of breast and ovarian cancer among women with inherited mutations in the BRCA1 or BRCA2 genes, according to one of the largest prospective studies on the subject to date. The findings , published September 1, 2010, in JAMA, provide estimates of the benefits of mastectomy and salpingo-oophorectomy (removal of the ovaries and fallopian tubes) in reducing the risk of cancer and death among carriers of disease-associated BRCA1 or BRCA2 gene mutations. These mutations confer a 56 to 84 percent lifetime risk of breast cancer.
The results also show that the risk reduction occurs regardless of whether the mutation is located in the BRCA1 or BRCA2 gene or whether a woman had cancer previously. Researchers at 22 medical centers in Europe and North America tracked nearly 2,500 women with a disease-associated BRCA1 or BRCA2 mutation. Almost half of the women had one of the prophylactic surgeries.
During 3 years of follow-up, none of the women who had a mastectomy developed breast cancer, while 7 percent of the women who didn’t have the surgery were diagnosed with breast cancer. And only 1 percent of the women who underwent risk-reducing salpingo-oophorectomy developed ovarian cancer during 6 years of follow-up, compared with 6 percent of women who did not have the surgery.
“This study reinforces the message that genetic testing has value,” said Timothy Rebbeck, Ph.D., of the University of Pennsylvania, the study’s senior author. Women who know that they have inherited a high-risk mutation can, with the appropriate genetic counseling, take steps to reduce their risk of cancer through prophylactic surgery, he continued.
Although many women choose prophylactic surgery, many do not, the study authors noted. Just 10 percent of the women in the study chose prophylactic mastectomy and 38 percent chose salpingo-oophorectomy. “For women who have these genetic mutations, we think we can save lives,” Dr. Rebbeck stressed. “And that’s an important message.”
The authors of an accompanying editorial in JAMA echoed this message and noted that options for prophylactic surgeries have changed and improved. For example, laparoscopic salpingo-oophorectomy is a relatively low-risk procedure that can be done in an outpatient setting, while new techniques for mastectomy produce a more natural appearance, wrote Laura Esserman, M.D., of the University of California, San Francisco, and Virginia Kaklamani, M.D., of Northwestern University.