Impact of breast reconstruction on the decision to undergo contralateral prophylactic mastectomy

Background. In the last decade, there has been increasing use of contralateral prophylactic mastectomy (CPM) in patients with unilateral breast cancer and ductal carcinoma-in-situ (DCIS) undergoing mastectomy. Although many factors have been proposed to explain this trend, the impact of breast reconstruction on CPM has not been studied. Methods. A retrospective review of patients with unilateral invasive breast cancer or DCIS from Surveillance, Epidemiology, and End Results registry data (2004-2008) was conducted. Characteristics of patients undergoing CPM and reconstruction were evaluated. Results. A total of 102,674 patients diagnosed with DCIS or stage I to III infiltrating breast cancer underwent mastectomy for their primary lesion. Of these, 16,197 patients (16 %) underwent a CPM. A significantly higher proportion of women undergoing CPM had reconstruction performed (46 %) than those patients not undergoing CPM (15 %) (p < 0.001). Of the 20,760 patients (20 %) who underwent reconstruction, 7410 (36 %) had implant reconstruction, 7705 (37 %) tissue reconstruction, and 1941 (9 %) combined tissue/implant reconstruction; there were no data for 3,702 (18 %). There was an increasing trend of patients undergoing reconstruction from 2004 (n = 3390, 16.3 %) to 2008 (n = 5406, 26 %) (p < 0.001). On multivariable analysis, significant variables predicting CPM included age <45 years, stage I disease (odds ratio [OR] 1.44, 95 % confidence interval [CI] 1.35-1.54), lobular histology (OR 1.15, 95 % CI 1.11-1.20), and undergoing breast reconstruction (OR 3.58, 95 % CI 3.41-3.75). Conclusions. Besides age, undergoing reconstructive surgery is the factor most strongly associated with CPM. This suggests that apart from risk reduction, the availability of and/or patient willingness to undergo breast reconstruction may influence the decision to undergo CPM.