Subpectoral Implant Placement Is Not Protective against Postmastectomy Radiotherapy-Related Complications Compared to Prepectoral Placement

Abstract

Background: Postmastectomy radiotherapy (PMRT) is associated with altered cosmetic outcomes and higher complication rates in implant-based breast reconstruction (IBR). Conventional wisdom suggests that muscle coverage is somewhat protective against PMRT-related complications. In this study, the authors compared surgical outcomes in patients who underwent two-stage prepectoral versus subpectoral IBR in the setting of PMRT. Methods: The authors performed a retrospective cohort study of patients who underwent mastectomy and PMRT with two-stage IBR from 2016 to 2019. The primary outcome was breast-related complications, including device infection; the secondary outcome was device explantation. Results: The authors identified 179 reconstructions (101 prepectoral and 78 subpectoral) in 172 patients with a mean follow-up time of 39.7 ± 14.4 months. There were no differences between the prepectoral and subpectoral reconstructions in rates of breast-related complications (26.7% and 21.8%, respectively; P = 0.274), device infection (18.8% and 15.4%, respectively; P = 0.307), skin flap necrosis (5.0% and 1.3%, respectively; P = 0.232), or device explantation (20.8% and 14.1%, respectively; P = 0.117). In adjusted models, compared with prepectoral device placement, subpectoral device placement was not associated with a lower risk of breast-related complications [hazard ratio (HR), 0.75; 95% confidence interval (CI), 0.41 to 1.36], device infection (HR, 0.73; 95% CI, 0.35 to 1.49), or device explantation (HR, 0.58; 95% CI, 0.28 to 1.19). Conclusions: Device placement plane was not predictive of complication rates in IBR in the setting of PMRT. Two-stage prepectoral IBR provides safe long-term outcomes with acceptable postoperative complication rates comparable to those with subpectoral IBR, even in the setting of PMRT. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.