When Angelina Jolie decided to share her personal story about undergoing a double mastectomy to reduce her risk of breast cancer, many applauded her candidness and appreciated her decision. "My doctors estimated that I had an 87 percent risk of breast cancer and a 50 percent risk of ovarian cancer, although the risk is different in the case of each woman," Jolie wrote in a New York Times Op-Ed piece. "Once I knew that this was my reality, I decided to be proactive and to minimize the risk as much I could. I made a decision to have a preventive double mastectomy."

Many women who have breast cancer in one breast will oftentimes opt for a preventive mastectomy for the other. The question is: Does this operation actually work in preventing breast cancer? Not necessarily. According to a study published in JAMA Surgery, removing the unaffected breast has not been shown to reduce the risk of developing breast cancer in that breast.

"The growing rate of CPM has motivated some surgeons to question whether performing an extensive operation that is not clinically indicated is justified to reduce the fear of disease recurrence,” said study author Dr. Sarah T. Hawley from the University of Michigan Medical School, Ann Arbor. “Increased attention by surgeons coupled with decision tools directed at patients to aid in the delivery of risk and benefit information and to facilitate discussion could reduce the possibility of overtreatment in breast cancer.”

For the study, researchers conducted a survey on 2,290 women newly diagnosed with breast cancer and reported their diagnosis to the Detroit and Los Angeles Surveillance, Epidemiology and End Results (SEER) registries from June 2005 to February 2007; and again four years later, from June 2009 to February 2010, according to a news release.

They found that out of the 1,447 women who were surveyed, 18.9 percent “strongly considered” contralateral prophylactic mastectomy (CPM), a procedure used to remove both breasts, and 7.6 percent actually underwent the procedure. To break this down even further, out of those who strongly considered the procedure, over 45 percent actually went through with the removal of one breast and 22.8 percent had their tumors removed, but not the entire breast.

The authors also found that many of the patients who had the CPM had no genetic or family risk factors — 80 percent reported they had the procedure to prevent breast cancer in the other breast (even if there was no sign of the cancer developing). Furthermore, the study found that women who were more educated were more likely to have a double mastectomy.

Despite these apprehensions with CPM, this might open doors to discussion surrounding different treatment options and to show support. “Not only should pros and cons of different treatment options be communicated, but there needs to be consideration of the patient's personal circumstances and perceptions, all the while addressing anxiety and concerns about breast cancer recurrence and new primary disease (and the distinction between the two),” Shoshana M. Rosenberg and Dr. Ann H. Partridge from the Dana-Farber Cancer Institute, Boston, stated in the news release. “Finding balance around this issue, like the decision process itself, should be a goal shared by patients and clinicians alike.”

Source: Hawley ST, et al. Study Examines Prophylactic Double Mastectomy Following Breast Cancer Diagnosis. JAMA Surgery. 2014.