A Critical Appraisal of Late Complications of Prepectoral versus Subpectoral Breast Reconstruction Following Nipple-Sparing Mastectomy.

[BACKGROUND] Nipple-sparing mastectomy (NSM) offers improved aesthetics without compromising oncologic safety. Subpectoral breast reconstruction has long been standard practice, although prepectoral reconstruction has recently resurged in popularity. Due to this recent paradigm shift, studies comparing long-term outcomes by reconstructive plane are lacking.

[METHODS] A retrospective review was conducted on consecutive NSMs with implant-based reconstruction in either the prepectoral or subpectoral plane from 2014 to 2018. Patient demographics, implant specifications, and operative details were collected to evaluate primary outcomes of prosthetic failure and unplanned reoperations by reconstructive plane. Secondary outcomes included animation deformity, capsular contracture, rippling, plane change, and minor revisions, including fat grafting. Bivariate and multivariate analyses were performed to assess outcomes.

[RESULTS] Overall, 405 NSMs were performed on 228 women (subpectoral = 202, prepectoral = 203), with a mean follow-up of 2.1 years (standard deviation 1.1). During the study period (2014-2018), a shift from subpectoral to predominantly prepectoral mastectomies occurred in 2017. Prepectoral reconstructions were more often direct-to-implant (DTI) compared with subpectoral (73.9% vs. 33.2%, p < 0.001). Prepectoral reconstruction demonstrated significantly reduced prosthetic failure (odds ratio [OR] 0.30, 95% confidence interval [CI] 0.14-0.65) and unplanned reoperations (OR 0.43, 95% CI 0.24-0.77) compared with subpectoral reconstruction after controlling for implant characteristics and other possible confounders. Prepectoral patients experienced decreased animation deformity overall (19.7% vs. 0.0%, p < 0.001), with plane changes seen in 10.6% of subpectoral reconstructions for animation deformity correction. Prepectoral patients experienced an increase in rippling (15.3% vs. 6.1%, p = 0.003) without a significant increase in fat grafting (subpectoral = 11.6% vs. prepectoral = 12.3%, p = 0.829).

[CONCLUSIONS] This single-institution experience compares late complications of prepectoral and subpectoral implant-based reconstruction following NSM. Prepectoral reconstruction can be safely performed with improved understanding of mastectomy planes, readily affords DTI reconstruction, and reduces animation deformity at the expense of rippling.