Double Mastectomy Doesn't Improve Survival, Study Finds
TUESDAY, Sept. 2, 2014 -- More U.S. women with early stage breast cancer are choosing to have both breasts removed as a precautionary step, although the double mastectomy provides no apparent survival advantage, researchers say.
Death rates are similar for women who have both breasts taken off and those who opt for breast-conserving surgery known as lumpectomy, according to their new study.
"We found no lower death rates among women who had bilateral mastectomy compared to women who had breast-conserving surgery with radiation," said study researcher Scarlett Gomez, a research scientist at the Cancer Prevention Institute of California.
The results are important for women at average risk of breast cancer, Gomez and other experts said.
Tracking health data on more than 189,000 breast cancer patients in California, researchers found that the number of women opting for double -- or bilateral -- mastectomy jumped from 2 percent in 1998 to 12.3 percent in 2011.
One-third of women younger than 40 opted for a double mastectomy in 2011, compared to less than 4 percent at the study's start, the researchers said.
The study, published Sept. 3 in the Journal of the American Medical Association, followed most of the patients for at least seven years.
The preventive, or prophylactic, double mastectomy has been in the spotlight recently. In 2013, actress Angelina Jolie announced she had had a preventive double mastectomy because of a strong family history of breast and ovarian cancer. She'd also tested positive for the genetic mutation BRCA1, which raises breast cancer risk.
Gomez said her team realized the proportion of women opting for double mastectomy had surged in recent years and wanted to see what effect the more extensive surgery had on survival. The radical surgery is associated with higher costs, longer recovery and greater risk of complications.
Using information from a California cancer registry, they looked at survival after double mastectomy, breast-conserving therapy (lumpectomy) with radiation, and single mastectomy (removal of one breast) in women who had early cancer in one breast. The registry didn't include genetic information that might have indicated raised breast cancer risk.
Death rates were similar between women having double mastectomy and breast-conserving surgery, the researchers said. However, the death rate associated with single mastectomy was higher than the other procedures. "That is not a new finding," Gomez said. The higher rate is thought to be linked with other factors, such as the presence of other health conditions.
Over 10 years, survival was 83 percent for those who had lumpectomy, 81 percent for those who underwent double mastectomy and nearly 80 percent for a single mastectomy.
The findings echo those of other recent studies, Gomez said.
Women need this information when deciding on the surgical treatment of their breast cancer, Gomez said.
Oftentimes, survival rates are just one of many factors a woman considers when weighing surgical treatment for breast cancer, she said. A common reason for double mastectomy is fear of cancer recurrence, even though the fear usually exceeds the estimated risk, she said.
For some women, aesthetics are a key consideration, the researchers wrote. Some newer reconstruction techniques produce better breast symmetry if both are reconstructed at the same time.
Being informed is essential, said Dr. Lisa Newman, director of the Breast Care Center at the University of Michigan, who wrote an editorial accompanying the study. "Overall, I think the important message [from this study] for our breast cancer patients is there is no overwhelming survival advantage," she said.
As long as women understand the pros and cons of the procedures, "it really does become a very personal choice," she added.
Dr. Len Lichtenfeld, deputy chief medical officer for the American Cancer Society, agreed. Doctors need to communicate these study findings to their patients who are deciding about surgical treatment of their breast cancer, he said.
Lichtenfeld, who had no part in the study, advises women to take time after their diagnosis to learn about the pros and cons of each approach.
No matter which option she chooses, a woman's decision about surgical treatment needs to be respected, Lichtenfeld said. "If a woman is educated [about her options] and makes a decision, that is her decision."
For more about surgical options for breast cancer, visit the American Cancer Society.
Posted: September 2014