Increasingly, women with early-stage breast cancer are opting for an aggressive operation to remove both breasts, known as contralateral prophylactic mastectomy (CPM). New research findings suggest that having the healthy breast removed may not provide a survival benefit for women with cancer in only one breast. This research was presented at the 2013 Clinical Congress of the American College of Surgeons in Washington, DC.
According to the American Cancer Society, breast cancer is diagnosed in more than 232,000 women in the United States every year, making breast cancer the second most common type of cancer in women, after skin cancer. Many women who face this diagnosis worry about cancer recurring in the healthy breast and therefore choose to have both breasts removed, even though the risk of developing cancer in the other breast is very low. Women at high risk include those with a family history of breast or ovarian cancer and women who test positive for the BRCA1 and BRCA2 gene mutations.
Importantly, until now no study has looked at the decision-making processes that lead women to choose CPM. “There have been several studies in the last couple of years indicating that there may be a survival benefit for selected patients by having their healthy breast removed,” said study coauthor Todd M. Tuttle, MD, FACS, chief of surgical oncology, University of Minnesota, Minneapolis. “This research will provide physicians and patients with accurate and easily understood information about whether removal of the healthy breast will impact their survival at all.”
To better understand the effect of CPM on life expectancy, the researchers conducted an analytic modeling study among women without a BRCA gene mutation. Within this group, the researchers compared women who underwent CPM with women who did have early-stage breast cancer in one breast and no prophylactic operation to remove the other breast.
For the study, the researchers estimated the life expectancy gain of CPM among subgroups of women with new cancer diagnoses in one breast by age 40 to 60 years, estrogen receptor status as positive or negative, and stage I or II cancer. They found that the maximum life expectancy gain for women who underwent CPM was 6 months for all scenarios including age, estrogen receptor status, and cancer stage groups.
Because many women are driven by their fears of contracting a second cancer in their healthy breast, they choose a double mastectomy, the more aggressive treatment. This procedure is a bigger operation associated with a longer recovery period and potentially more complications. Thus, experts are concerned that some patients are being overtreated with a prophylactic procedure.
“I think this decision model study will provide women who are considering these extensive operations with more accurate information about whether or not CPM is going to improve their survival,” Tuttle said. He explained that these results can help to educate women that a contralateral mastectomy will not improve their survival rate if they do not have hereditary breast cancer.