Prepectoral versus Submuscular Implant-Based Breast Reconstruction: A Matched-Pair Comparison of Outcomes

Background: Implant-based breast reconstruction is the most common reconstructive approach after mastectomy. Prepectoral implants offer advantages over submuscular implants, such as less animation deformity, pain, weakness, and postradiation capsular contracture. However, clinical outcomes after prepectoral reconstruction are debated. The authors performed a matched-cohort analysis of outcomes after prepectoral and submuscular reconstruction at a large academic medical center. Methods: Patients treated with implant-based breast reconstruction after mastectomy from January of 2018 through October of 2021 were retrospectively reviewed. Patients were propensity score exact matched to control demographic, preoperative, intraoperative, and postoperative differences. Outcomes assessed included surgical-site occurrences, capsular contracture, and explantation of either expander or implant. Subanalysis was done on infections and secondary reconstructions. Results: A total of 634 breasts were included (prepectoral, 197; submuscular, 437). A total of 292 breasts were matched (146 prepectoral:146 submuscular) and analyzed for clinical outcomes. Prepectoral reconstructions were associated with greater rates of SSI (prepectoral, 15.8%; submuscular, 3.4%; P < 0.001), seroma (prepectoral, 26.0%; submuscular, 10.3%; P < 0.001), and explantation (prepectoral, 23.3%; submuscular, 4.8%; P < 0.001). Subanalysis of infections revealed that prepectoral implants have shorter time to infection, deeper infections, and more Gram-negative infections, and are more often treated surgically (all P < 0.05). There have been no failures of secondary reconstructions after explantation in the entire population at a mean follow-up of 20.1 months. Conclusions: Prepectoral implant-based breast reconstruction is associated with higher rates of infection, seroma, and explantation compared with submuscular reconstructions. Infections of prepectoral implants may need different antibiotic management to avoid explantation. Secondary reconstruction after explantation can result in long-term success. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.