Oncological safety and complication risks of mastectomy with or without breast reconstruction: A Bayesian analysis.

BACKGROUND: Currently, breast cancer patients undergoing mastectomy (MA) have three surgical options: MA only and reconstruction at the time of MA ("immediate," IBR) or at a later time ("delayed," DBR). To assess the oncological safety and complication risks associated with different surgical choices, a systematic review with Bayesian network analysis was conducted. METHODS: Cochrane library, PubMed/MEDLINE, EMBASE, and the China National Knowledge Infrastructure were systematically searched in November 2019. The odds ratios [OR] were estimated for oncological safety (including disease-free survival, overall survival, local recurrence, and distant metastases) and complication risks (including overall complications, surgical site infection, and lymphedema) among MA, IBR, and DBR groups. RESULTS: In the included 51 studies (265,522 patients), reconstruction after MA for IBR or DBR was associated with increased overall survival compared to simple MA (DBR vs. MA: OR 4.12, 95% credible interval [CrI] 1.80-10.01; IBR vs. MA: OR 1.75, 95% CrI 1.32-2.32). Additionally, IBR was associated with a decreased distant metastasis rate compared to MA (IBR vs. MA: OR 0.67, 95% CrI 0.51-0.90). However, the risk of overall complications and surgical site infection was higher in the IBR group than in the other two groups (complications, IBR vs. DBR: OR 1.40, 95% CrI 1.01-1.93; surgical site infection, IBR vs. MA: OR 1.77, 95% CrI 1.03-3.13). CONCLUSIONS: Evidence suggested that breast reconstruction, whether IBR or DBR, does not adversely affect oncological safety in the setting of breast cancer. IBR is associated with an increased risk of overall complications and surgical site infection, but technical advances in this surgical procedure have cumulated over time.