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.