Complications Associated with Contralateral Prophylactic Mastectomy: A Systematic Review and Meta-Analysis

No meta-analysis has examined whether contralateral prophylactic mastectomy increases complication risk for unilateral breast cancer patients undergoing unilateral mastectomy.Fifteen studies on complications of unilateral mastectomy plus contralateral prophylactic mastectomy met inclusion criteria. Meta-analyses compared complications of (1) diseased versus contralateral breasts in unilateral plus contralateral prophylactic mastectomy patients and (2) patients undergoing unilateral plus contralateral prophylactic mastectomy versus unilateral alone when grouped by reconstructive method.For all unilateral plus contralateral prophylactic mastectomy patients, the diseased breast was significantly more prone to complications versus the contralateral breast (relative risk, 1.24; p = 0.03). In studies that stratified by reconstructive method, the complication risk was significantly higher for unilateral plus contralateral prophylactic mastectomy versus unilateral mastectomy alone for patients with no reconstruction (relative risk, 2.03; p = 0.0003), prosthetic-based reconstruction (relative risk,1.42; p = 0.003), and autologous reconstruction (relative risk, 1.32; p = 0.005). The only prospective trial showed similar results, including for more severe complications. Smaller retrospective studies without stratification by reconstructive method showed similar complications for unilateral plus contralateral prophylactic mastectomy versus unilateral mastectomy alone (relative risk, 1.06; p = 0.70). These groups had similar incidences of complication-related delay in adjuvant therapy, as demonstrated by one study.After unilateral plus contralateral prophylactic mastectomy, diseased breasts are at higher risk for complications. Stronger evidence supports higher complication risk for unilateral plus contralateral prophylactic mastectomy than unilateral alone. More work is needed to determine the effect of complications on timing of adjuvant therapy.