Dermal Nipple-Areola Complex perfusion through full thickness circumareolar scars: a porcine model for safe delay in two-stage nipple sparing mastectomy

Nipple sparing mastectomy (NSM) has evolved to a standard surgical option. NSM complication rate remains high in large breasts. To reduce the risk of necrosis several authors propose delayed procedures to enhance blood supply to nipple-areola complex (NAC). The purpose of this study in a porcine model is to show adequate redirection of NAC perfusion by neoangiogenesis through circumareolar scars. Delayed two-staged NSM is simulated in 52 nipples (6 pigs) with a 60-days interval. The nipples undergo a full thickness circumareolar incision onto the muscular fascia with preservation of underlying glandular perforators. After 60 days NSM is performed through a radial incision. A silicone sheet is introduced in the mastectomy plane to prevent NAC revascularization by wound bed imbibition. Digital colour imaging is used to assess necrosis. Near-infrared fluorescence with indocyanine green (ICG) is used to assess perfusion patterns as well as perfusion in real time. No NAC necrosis is seen after 60 days delay in all nipples. In all nipples ICG-angiography shows complete alteration of NAC vascular perfusion pattern from subjacent gland to a capillary fill following devascularization exhibiting a predominant arteriolar capillary blush without distinct larger vessels.Conclusion: NAC delay reverses glandular perfusion to adequate dermal neovascularization. Neovascularization through full thickness scars provides sufficient dermal perfusion after 60 days delay. Identical staged delay in humans may be a surgically safe NSM option and could broaden therapeutic NSM indications in difficult breasts. Large clinical trials are necessary to provide identical results in human breasts.