Double Mastectomies Often Done for No Reason
Many women diagnosed with breast cancer in 1 breast eventually decide to have the other, healthy breast removed, in the mistaken belief that doing so will reduce their risk for recurrence.
While fear of recurrence appears to drive the decision to undergo the additional surgery, the fact is that relatively few women actually have a clinically significant risk of developing cancer in both breasts, say researchers writing in JAMA Surgery.
Moreover, contralateral prophylactic mastectomy (CPM) has not been shown to reduce the risk for recurrence, they add. “Women appear to be using worry about their cancer recurring as a reason to choose CPM, but this does not make sense because having a nonaffected breast removed will not reduce the risk of recurrence in the affected breast,” lead author Sarah T. Hawley, PhD, MBA, told Medscape Medical News.
The Angelina Jolie Factor
When the actress Angelina Jolie had both breasts removed as prophylaxis against developing breast cancer, the widespread media attention may have contributed to more women diagnosed with unilateral breast cancer opting to have the contralateral breast removed as well, Dr. Hawley noted.
“I think that certainly contributed to it, but the trend was already there before she had her surgery. The reason for this trend is related to fear and anxiety about having cancer, worry that it will come back, and having the opportunity to feel as if you are doing everything possible to prevent that, which unfortunately often means having more surgery,” she said.
Using Surveillance, Epidemiology, and End Results (SEER) registries in Detroit, Michigan, and Los Angeles, California, Dr. Hawley and her group surveyed 2290 women newly diagnosed with breast cancer from June 2005 to February 2007 and again 4 years later, from June 2009 to February 2010.
They asked the women whether they had received 1 of the following types of surgery: unilateral mastectomy, breast conservation surgery, or CPM.
The mean age of the women was 59.1 years (range, 25 to 79 years), 57% were married or had a partner, and 59% had at least some college education.
The researchers analyzed the responses of 1447 of the women who had been treated for breast cancer and who had not had a recurrence.
They found that 18.9% strongly considered CPM, and 7.6% received it.
The majority of the women (68.8%) who underwent CPM had no genetic or familial risk factors for contralateral breast cancer.
Eighty percent of the women who had CPM said they did so to prevent breast cancer in the other breast. Most of these women (85.9%) also had breast reconstruction surgery.
The researchers also found that of the 136 women who actually had a clinical indication for CPM, most (75.7%) elected not to have the procedure.
Women with more education were more likely to opt for CPM, and t having MRI at the time of diagnosis was associated with a greater likelihood of undergoing the additional surgery.
Younger women were also more likely to opt for CPM, Dr. Hawley said.
Rates of CPM “Inching Up”
The trend for having both breasts removed has been increasing, Dr. Hawley said.
“In the early to mid-90s, almost nobody was having that procedure done, certainly not at the rate that we are seeing now, and perhaps just in the women who have clinical indications for CPM. It just wasn’t something women would even think about, it was something that wouldn’t even make it into the data because the rate was so low. The fact that the rate is inching up is a cause for further investigation to try and understand what’s going on,” she said.
Ann H. Partridge, MD, MPH, from the Dana Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts, told Medscape Medical News that doctors should be informing patients about their risks at the time of diagnosis.
Dr. Partridge coauthored an accompanying editorial with colleague Shoshana M. Rosenberg, ScD, MPH. They write, “An underlying tension exists between ‘do no harm,’ viewing CPM as medically unnecessary given the lack of demonstrated benefit on recurrence and survival, and respect for patient preferences and autonomy.”
Elaborating In an interview with Medscape Medical News, Dr. Partridge said, “Ideally, clinicians should be telling their patients fully about their risks of disease, including recurrence in the affected breast, new primary in the unaffected breast, as well as distant recurrence, which is usually the greatest risk and the one we give chemo and hormonal therapy for when needed.”
The lack of clear survival advantage from taking off the unaffected side needs to be clarified, Dr. Partridge said.
However, for some women, “it makes sense to do this anyway. Regardless, all of this needs to be in a setting where anxiety is addressed and managed with the patient, otherwise it will be difficult for her and her loved ones to digest any of it,” she said.
Women who have a genetic predisposition to breast cancer (eg, those with BRCA1 or BRCA2 mutations or who have other high risk factors for a new breast cancer in the other breast, such as having had radiation to the chest), are often counseled to consider bilateral mastectomy at the time of a breast cancer diagnosis because the risk for a new primary cancer is so high, about 20% in the next 5 years compared with about 2.5% in the average survivor, she said.
Dr. Partridge added that the decision to undergo CPM is a “very personal one for a woman and her loved ones to make, with lots of factors both medical and psychological that play into it.”
The study was funded by grants to the University of Michigan from the National Institutes of Health. Dr. Hawley, Dr. Rosenberg, and Dr. Partridge have disclosed no relevant financial relationships.
JAMA Surg. Published online May 21, 2014.