Evidence-Based Information Should Guide Prophylactic Mastectomy Decisions

Katharine Yao, MD

One of the first studies to prospectively examine women’s breast surgery preferences has revealed that newly diagnosed women with breast cancer who decide to undergo contralateral prophylactic mastectomy (CPM) aren’t relying on evidence-based information, highlighting the need for interdisciplinary patient education and communication. Results of the study were presented at the ASCO Breast Cancer Symposium held September 4-6, 2014 in San Francisco. Abstract 71

“There is so much information about breast cancer that it’s easy for patients to get overwhelmed. As doctors, we have to be aware of each patient’s knowledge level and the concerns and worries he or she have,” said lead study author Katharine Yao, MD, director of the breast surgical program at NorthShore University HealthSystem, Evanston, Illinois, and a clinical associate professor of surgery at the Pritzker School of Medicine, University of Chicago. “And we need to do a better job of educating patients that the risk of developing contralateral breast cancer is actually low and that breast cancer can come back in other parts of their body no matter what type of surgery they have.”

Researchers administered a 55-item survey to 150 newly diagnosed breast cancer patients at two institutions prior to their surgery—but after they had made their decision as to type of procedure—to compare patient knowledge, perception, and anxiety factors amongst those who considered a CPM versus those who did not.

Eighty-three patients (58%) wanted or considered a CPM upon initial diagnosis, whereas 35 patients (24.6%) knew that they did not want a CPM upon initial diagnosis. Sixteen patients (11.3%) said that they knew about CPM but did not think it was an option for them, and 8 patients (5.6%) did not have any knowledge of CPM.

Patients were asked a knowledge-based question: Does removing a healthy breast reduce the chance that the cancer will come back? Thirty-two percent of the patients who considered CPM and 53% of patients who did not consider CPM said that this statement was correct. Another question measured anxiety levels and asked patients: How much do you worry about getting cancer elsewhere in your body? Forty-three percent of women considering CPM responded that they were very much/extremely worried about this, versus 11% of those not considering CPM.

“These data demonstrate that this complex decision is often the result of higher anxiety levels and worry about recurrence,” Yao said. “These are certainly valid concerns, but as oncologists we need to make certain that we are educating each patient about her individual risk for the future.”