Performance of Human and Porcine Derived Acellular Dermal Matrices in Prepectoral Breast Reconstruction: A Long-term Clinicaland Histologic Evaluation

Human acellular dermal matrices (ADMs) remain the most used matrices in prosthetic breast reconstruction. However, the availability and cost of ADMs limit their use in prepectoral reconstruction-which requires large amounts of ADM-and alternative matrices are therefore being explored. The aim of this study was to demonstrate the safety and efficacy of human-porcine ADM constructs via clinical outcomes and histologic evidence of graft integration. Consecutive patients undergoing tissue-expander/implant reconstructions with human-porcine ADM constructs were included. Biopsies of both ADMs were obtained at expander/implant exchange and evaluated for cellularization, vascularization, and inflammation. Postoperative complications were retrieved from patient records. Fifty-nine patients met the inclusion criteria. Mean [standard deviation] follow-up was 6.7 [0.56] years; minimum follow-up was 5 years. Any complication rate was 8.6%, including skin necrosis (6.9%), seroma (1.7%), expander/implant exposure (1.7%), and return to the operating room (2.6%). A total of 138 ADM biopsy specimens were obtained from 38 patients at expander/implant exchange. Histologic analyses revealed lower fibroblast infiltration and vascularization and higher inflammatory response in porcine vs human ADM specimens, consistent with published results in nonhuman primates. Despite these differences, there were no cases of graft rejection, capsular contracture, or expander/implant loss. Porcine ADM performs clinically in a similar manner to human ADM, albeit with minor differences in cellular ingrowth and vascularization, suggesting that it may be an alternative to human ADM in prepectoral breast reconstruction.