Assessing the additional surgical risk of contralateral prophylactic mastectomy and immediate breast implant reconstruction.

[INTRODUCTION] There has been a sharp rise in the rate of contralateral prophylactic mastectomy over the last decade, despite the low incidence of new primary cancers predicted for the contralateral breast. This study compares the postoperative complication rates between the diseased breast treated with mastectomy and the contralateral breast that underwent prophylactic mastectomy, followed by immediate bilateral breast implant reconstruction. We hypothesized that there will be no difference in postoperative outcomes between prophylactic and diseased groups, as the surgical approach would be comparable.

[METHODS] After IRB approval, a retrospective chart review identified consecutive unilateral breast cancer patients who underwent bilateral mastectomy and immediate breast reconstruction between May 2008 and May 2018 at a tertiary academic medical center. A paired sample t-test and a penalized logic regression model were constructed to identify relationships between breast laterality and outcomes.

[RESULTS] A total of 1117 patients with unilateral breast cancer who underwent bilateral mastectomy and immediate breast implant reconstruction were identified. Rates of capsular contracture and infection were significantly greater in the diseased breast, while rates of revision were significantly greater in the contralateral prophylactic breast. There were no statistically significant differences between breasts in rates of explant, skin flap necrosis or hematoma. When adjusted for confounding variables, a higher infection rate was observed in the diseased breast.

[CONCLUSION] This study detected significant differences in postoperative complication rates between the diseased and prophylactic breasts following bilateral mastectomy and immediate breast implant reconstruction. Postoperative complications occurred more frequently in the diseased breast compared with low rates of complications in the contralateral prophylactic breast. This information is helpful for preoperative decision making, as surgeons and patients carefully weigh the additional risks of contralateral prophylactic procedure.