Viability of acellular biologic graft for nipple-areolar complex reconstruction in a non-human primate model.

Many of the > 3.5 million breast cancer survivors in the US have undergone breast reconstruction following mastectomy. Patients report that nipple-areolar complex (NAC) reconstruction is psychologically important, yet current reconstruction techniques commonly result in inadequate shape, symmetry, and nipple projection. Our team has developed an allogeneic acellular graft for NAC reconstruction (dcl-NAC) designed to be easy to engraft, lasting, and aesthetically pleasing. Here, dcl-NAC safety and host-mediated re-cellularization was assessed in a 6-week study in rhesus macaque non-human primates (NHPs). Human-derived dcl-NACs (n = 30) were engrafted on the dorsum of two adult male NHPs with each animal's own nipples as controls (n = 4). Weight, complete blood counts, and metabolites were collected weekly. Grafts were removed at weeks 1, 3, or 6 post-engraftment for histology. The primary analysis evaluated health, re-epithelialization, and re-vascularization. Secondary analysis evaluated re-innervation. Weight, complete blood counts, and metabolites remained mostly within normal ranges. A new epidermal layer was observed to completely cover the dcl-NAC surface at week 6 (13-100% coverage, median 93.3%) with new vasculature comparable to controls at week 3 (p = 0.10). Nerves were identified in 75% of dcl-NACs (n = 9/12) at week 6. These data suggest that dcl-NAC is safe and supports host-mediated re-cellularization.