Surgeons, not clinical factors, accounted for 20% of variation in rates of contralateral prophylactic mastectomy (CPM), according to the results of a large survey study.
Only 4% of patients elected CPM when their surgeons were among those who least favored it overall and most preferred breast-conserving treatment, according to Steven J. Katz, MD, MPH, of the University of Michigan, Ann Arbor, and his associates. But 34% of patients chose CPM when their surgeons least favored BCT and were most willing to perform CPM, the researchers found. “Attending surgeons exert strong influence on the likelihood of receipt of CPM after diagnosis of breast cancer,” highlighting “the need to help surgeons address this growing clinical conundrum in the examination room,” they wrote (JAMA Surg. 2017 Sep 13. doi: 10.1001/jamasurg.2017.3415).
Rates of CPM have risen markedly in the United States although it has not been shown to confer a survival advantage for average-risk women. To examine how surgeons themselves affected rates of CPM, the investigators sent surveys to 7,810 women treated for stage 0 to II breast cancer from 2013 to 2015 and included in the Surveillance, Epidemiology, and End Results (SEER) registries of Georgia and Los Angeles County. (Among the 7,810 women, 507 were ineligible.) The researchers also surveyed 488 attending surgeons of these patients.
Response rates were high – 70% among patients (5,080 of 7,303) and 77% (377 of 488) among surgeons, the investigators reported. The average age of the patients was 62 years; 28% had an elevated risk of second primary cancer, and 16% underwent CPM. Patients whose surgeons’ rates of CPM exceeded the mean by at least one standard deviation had nearly threefold greater odds of undergoing CPM themselves (odds ratio, 2.8; 95% confidence interval, 2.1-3.4) regardless of age, date of diagnosis, BRCA mutation status, or risk of second primary cancer.
“One quarter of the surgeon influence was explained by attending attitudes about initial recommendations for surgery and responses to patient requests for CPM,” the researchers wrote. Additional predictors of CPM included elevated risk of second primary breast cancer, BRCA mutation, and younger age.
“We observed a range of reasons why a surgeon would be willing to perform CPM if asked: give peace of mind, yield better cosmetic outcomes, avoid conflict with patient, reduce need for surveillance, improve long-term quality of life, reduce recurrence of invasive disease, avoid losing patient to another surgeon, or improve survival (in order of endorsement),” the researchers wrote. “Our findings reinforce the need to address better ways to communicate with patients with regard to their beliefs about the benefits of more extensive surgery and their reactions to the management plan including surgeon training and deployment of decision aids.”
The National Cancer Institute provided funding. The researchers reported having no conflicts of interest.