Overestimating the risk that cancer in one breast will affect the other breast may cause many young women with breast cancer to choose contralateral prophylactic mastectomy even though most know it does not clearly improve survival. In a survey of 123 women who were diagnosed with cancer in one breast and chose to have a bilateral mastectomy, only 18% responded that women with breast cancer who undergo contralateral prophylactic mastectomy live longer, but when rating factors that were extremely or very important factors in their own decision to have contralateral prophylactic mastectomy, 98% indicated a desire to reduce their risk of contralateral breast cancer and 94% a desire to improve survival.

Peace of mind was also considered extremely or very important by 95% of women responding. The survey results were published in the Annals of Internal Medicine¹ and reported by major news and medical media.

“By raising awareness of the extent to which people seem to misperceive their risks, these data may have an impact on clinical practice,” study coauthor Eric P. Winer, MD, said in an interview with The ASCO Post. “If doctors are aware of these misperceptions, they can proactively address them.” Dr. Winer is Chief of the Division of Women’s Cancers and Director of the Breast Oncology Center at Dana-Farber Cancer Institute and Professor of Medicine at Harvard Medical School in Boston.

Proactively addressing the issue could include fully explaining to patients and families the low risks of developing contralateral breast cancer in most women (those without BRCA1 or BRCA2 mutations), as well as the risks and possible adverse effects of additional surgery and breast reconstruction.

Misperception of Risk

The survey results indicate that women who are not at increased risk for contralateral breast cancer because of genetic mutations overestimate the actual risk, “estimating that a median of 10 women out of 100 would develop contralateral breast cancer without contralateral prophylactic mastectomy within 5 years, which exceeds the actual risk of approximately 2% to 4% over 5 years,” the study authors reported. 

Women with mutations of BRCA1 (18% of patients surveyed) or BRCA2 (7%) more accurately perceived their risk for contralateral breast cancer, estimating that a median of 20 women out of 100 would develop contralateral breast cancer without contralateral prophylactic mastectomy within 5 years. A recent study cited by the authors found a 10-year cumulative risk of 24% to 31% among young women with a family history of breast cancer and a BRCA1 or BRCA2 mutation.²

Dr. Winer said that the more accurate perceived risk among the gene mutation carriers could be attributed to “the benefits of meeting with a genetic counselor, because most of them do. Maybe it is also the benefit of having more information available on the internet and among breast cancer survivors, family members, and friends.”

Competing Risk

The greatest risk for young women with breast cancer is from systemic recurrence and death from their initial breast cancer, and contralateral prophylactic mastectomy is not likely to alter this competing risk. The misperception among many women about breast cancer risk “points to a need for better risk communication strategies in an effort to ensure that treatment decision-making is truly evidence-based while remaining patient-centered,” the study authors concluded.

For a woman with a known BRCA1 or BRCA2 mutation, “particularly if it is someone who has a low risk of dying from her initial breast cancer, having the other breast removed would seem to be a rational approach,” Dr. Winer said. “The conversation that is hard is when someone has a very high-risk initial cancer and you are dealing with the fact that there is a huge competing risk that the woman will unfortunately have a recurrence and ultimately die from her first cancer, making anything you do on the other side much less relevant. That is a hard conversation and it is one that people have a hard time understanding at times,” he noted.

“The way I usually explain it is, the main event at the moment is the cancer you have. Let us get through this,” Dr. Winer continued. “Let’s see how you do over the next several years, and then we will, if necessary, address your concerns about your other breast.”

Overall Satisfaction High

The women completing the survey were diagnosed with breast cancer at age 40 or younger and were participants in an ongoing prospective cohort study to explore biologic, medical, and quality-of-life issues specific to young women. They received surveys twice a year for the first 3 years after diagnosis and then annually for an additional 7 years. Women who reported a bilateral mastectomy on any survey within 1 year after diagnosis received the supplementary contralateral prophylactic mastectomy questionnaire with 23 items related to decision-making, knowledge, risk perceptions, and worry about breast cancer.

“Overall satisfaction with the decision was high: 80% of women were extremely confident in their decision to have [contralateral prophylactic mastectomy], and 90% of respondents would have definitely chosen [contralateral prophylactic mastectomy] if deciding again,” according to the study report.

Some Outcomes Worse Than Expected

Despite the high overall rate of satisfaction with contralateral prophylactic mastectomy, several outcomes were worse than expected. These included a higher number of surgeries or procedures than expected, reported by 33% of those responding. In addition, 28% reported that numbness or tingling in the chest was worse than expected, 42% reported that their sense of sexuality was worse than they expected after surgery, and 31% reported being more self-conscious about their appearance than expected.

Problems such as numbness and tingling, “to a large extent are things people have to live with. A lot of that is a result of axillary surgery rather than breast surgery,” Dr. Winer said. “I think it is really difficult to know whether the problems people cite related to sexuality are attributable to having had bilateral mastectomies. We wouldn’t for a second say that this is causal,” he added.

Appearance Issues

“I generally tell patients that when you choose to have reconstruction, it is like adding another medical problem to your list of medical problems, because you either are moving some piece of your body where is wasn’t intended to be, or you are going to have an implant. And while implants are safe, we know that they can at times need to be replaced. Particularly in women who are going to need postmastectomy radiation, which is done quite frequently when patients have positive lymph nodes, the implant can lead to fibrosis and the cosmetic appearance is not necessarily going to be particularly good,” Dr. Winer explained.

Even for women considering a single mastectomy in the breast with cancer, “if a woman can have a lumpectomy, and I know that even if she has a mastectomy, she is going to wind up getting radiation or there is a high chance of it, I try to talk her out of having a mastectomy,” Dr. Winer said, because of the effect of the radiation on the appearance of the reconstructed breast.

“Another procedure that is done with a fair amount of frequency these days,” Dr. Winer said, “and that should be fully explained to those considering it, is a nipple-sparing mastectomy. The entire breast is removed except for the nipple, the areola complex, with the idea is that it looks a little bit more natural,” Dr. Winer commented. “But it is an insensate nipple. And it doesn’t always stay looking quite the same way once you remove all the breast tissue” and the nipple is on the reconstructed breast.

‘Bit of a Disconnect’

“There is a little bit of a disconnect in the responses to the survey in that the majority of people recognized that having a contralateral prophylactic mastectomy would not improve their survival, and yet still over 90% of the people cited improvement in survival as a reason for doing this,” Dr. Winer acknowledged.

“This discordance suggests some degree of cognitive dissonance,” Dr. Winer and coauthors wrote in the study report. “Most women acknowledge that [contralateral prophylactic mastectomy] does not improve survival, but anxiety and fear of recurrence probably influence women during the decision-making process, leading them to identify their desire to extend life and prevent metastatic disease as among the most important reasons for having [contralateral prophylactic mastectomy],” they said.

“The apparent discordance between patient perceptions and realistic expectations provides a teachable opportunity for physicians treating newly diagnosed patients with breast cancer,” Pamela R. Portschy, MD, and Todd M. Tuttle, MD, MS, of the University of Minnesota, Minneapolis, wrote in an accompanying editiorial.³ They also called on physicians to communicate the actual risk for contralateral breast cancer and the complications and alternatives to contralateral prophylactic mastectomy. “With improved patient education, perhaps the [contralateral prophylactic mastectomy] trends in the United States will plateau or be reversed,” they wrote.

According to the study report, contralateral prophylactic mastectomy rates “have increased dramatically among women treated for early-stage breast cancer in the United States,” from 4% to 6% in the late 1990s to between 11% and 25%. “It is interesting,” Dr. Winer said, “that at a time when we are seeing fewer second cancers because of the use of adjuvant hormonal therapy and when radiation is very effective after a lumpectomy in preventing a recurrence in the initial breast, that this is the time when we are now seeing this uptick in bilateral mastectomies.” ■

References

1. Rosenberg SM, Tracy MS, Meyer ME, et al: Perceptions, knowledge, and satisfaction with contralateral prophylactic mastectomy among young women with breast cancer. Ann Intern Med 159:373-381, 2013.

2. Reiner AS, John EM, Brooks JD, et al: Risk of asynchronous contralateral breast cancer in noncarriers of BRCA1 and BRCA2 mutations with a family history of breast cancer: A report from the Women’s Environmental Cancer and Radiation Epidemiology Study. J Clin Oncol 31:433-439, 2013.

3. Portschy PR, Tuttle TM: Contralateral prophylactic mastectomy: Perceptions versus reality. Ann Intern Med 159:428-429, 2013.