The use of contralateral prophylactic mastectomy tripled over 1 decade among women with invasive breast cancer despite evidence that the procedure does not improve survival compared with breast conservation, according to results of a SEER analysis.
“Our analysis highlights the sustained, sharp rise in popularity of contralateral prophylactic mastectomy [CPM] while contributing to the mounting evidence that this more extensive surgery offers no significant survival benefit to women with a first diagnosis of breast cancer,” Mehra Golshan, MD, distinguished chair in surgical oncology at Brigham and Women’s Hospital and medical director of International Oncology Programs at Dana-Farber/Brigham and Women’s Cancer Center, said in a press release. “Patients and caregivers should weigh the expected benefits with the potential risks of CPM including prolonged recovery time, increased risk of operative complications, cost, the possible need for repeat surgery and effects on self-image.”
Golshan and colleagues sought to update trends in CPM use and evaluate whether survival differed for patients based on hormone receptor status and age. They used the SEER database to identify 496,488 women diagnosed with unilateral stage I to III breast cancer between 1998 and 2012.
Overall, 59.6% of the cohort underwent breast-conserving surgery (BCS), 33.4% underwent unilateral mastectomy and 7% underwent CPM.
Women who underwent CPM were younger (median age, 50 years; BCS, 60 years; unilateral mastectomy, 59 years; P < .001), more likely to be non-Hispanic white (80.4% vs. 69.1%-75%) and more likely to have invasive lobular histology (12.7% vs. 7.1%-10.6%).
The proportion of women who underwent CPM significantly increased from 3.9% in 2002 to 12.7% in 2012 (P < .001). The rates of reconstructive surgery also increased in women who underwent CPM, from 35.3% in 2002 to 55.4% in 2012 (P < .001).
During this period, unilateral mastectomy was used less frequently (36.7% to 28.4%), whereas rates of BCS remained stable (59.4% to 58.9%).
Use of reconstructive surgery also was more common among women who underwent CPM than BCS (48.3% vs. 16%).
Despite increased use of CPM, analyses adjusted for age and other disease factors showed CPM did not improve breast cancer-specific survival (HR = 1.08; 95% CI, 1.01-1.16) or OS (HR = 1.08; 95% CI, 1.03.1.14) compared with BCS. This association persisted in subgroup analyses that evaluated outcomes based on hormone receptor status and age.
These results raise questions regarding why women opt for CPM. The procedure may be indicated for women with BRCA mutations, a family history of breast or ovarian cancer or a history of mantle-field radiation during childhood; however, only about a third of women who choose CPM have these risk factors, according to the press release.
“Women with unilateral breast cancer undergoing CPM continue to report a desire to extend life as one of the most important factors leading to their surgical decision,” Golshan said. “Understanding why women choose to undergo CPM may create an opportunity for health care providers to optimally counsel women about surgical options, address anxieties, discuss individual preferences and ensure peace of mind related to a patient’s surgical choice,” Golshan said. – by Nick Andrews
: One researcher reports institutional funding from Genentech and Puma for studies unrelated to this research. The other researchers report no relevant financial disclosures.