Reversed Acellular Dermis: Failure of Graft Incorporation in Primary Tissue Expander Breast Reconstruction Resulting in Recurrent Breast Cellulitis

Abstract

Sir: The use of acellular dermis in breast reconstruction has gained traction among patients. Despite its low overall complication rate, this procedure is not without risk; as with any foreign body, acellular dermis can generate a host inflammatory reaction and overt infection. The transition from inert graft to integrated tissue is dependent on vascularization and incorporation of the acellular dermis. The proper orientation of the graft is defined by placement of the dermal surface toward the vascularizing tissue. We present the first report of the clinical consequence of inadvertent placement of reversed acellular dermis during immediate expander breast reconstruction. The patient is a 60-year-old woman who underwent right skin-sparing mastectomy with sentinel lymph node biopsy, followed by immediate expander breast reconstruction with allograft acellular dermis (Flex-HD; Musculoskeletal Transplant Foundation, Edison, N.J.). There were no immediate postoperative complications. While receiving adjuvant chemotherapy, she had multiple episodes of self-limiting superficial cellulitis responsive to oral antibiotics. Ultrasound imaging revealed no evidence of fluid collection or abscess. At the routine expander/implant exchange procedure, intraoperative examination revealed capsule formation surrounding the acellular dermis graft, without significant tissue incorporation. On closer evaluation, the graft was noted to be reversed, with the tissue ingrowth dermal surface facing toward the expander. The unincorporated graft was removed. Postoperatively, the patient did not experience any further episodes of cellulitis. Pathologic evaluation of the dermal graft revealed dense foreign-body reaction without evidence of tissue revascularization (Fig. 1).Fig. 1.: Intraoperative and histologic evaluation of acellular dermal graft. (Above) Intraoperative image detailing reversed acellular dermis (grasped by tissue forceps) with absence of tissue incorporation. (Below) Histologic image of acellular dermal graft after removal detailing avascularity and inflammatory response.The incidence of cellulitis after tissue expander breast reconstruction is reportedly between 3 and 7 percent.1,2 Recently, within the breast literature, there have been reports of a latent clinical syndrome, termed “delayed breast cellulitis,” occurring months after the index mastectomy procedure.3 In our particular case, the patient did not have any of the risk factors for this syndrome. Several articles have also reported a longstanding erysipelas-like process that can occur following breast reconstruction.4 In these cases, resolution occurred gradually over months, without significant response to antibiotics. In our particular case, each episode of cellulitis was discrete, self-limited, and responsive to oral antibiotics. The transition from inert acellular dermal graft to host-integrated tissue is dependent on neovascularization of the graft, which reportedly occurs by week 12 after implantation.2 The proper orientation of the graft is dependent on matching the appropriate side of the graft to the vascularizing tissue. Electron microscopic studies indicate a demonstrable difference between acellular dermal graft surfaces: one that is more porous to enable cell infiltration and vascularization, and another that is more inert (Fig. 2). The lack of proper tissue ingrowth and revascularization is significant in our case, and suggests that graft orientation is crucial.Fig. 2.: Electron microscopic images of Flex-HD acellular dermal graft detailing the polarity differences of the graft surfaces. (Above) Porous “dermal” side, which effectively promotes incorporation and vascularization. (Below) Nonporous “epidermal” side, which is more inert. (Images courtesy of Dr. Bruce Ramshaw, Sheila Grant, and the BICAM materials team at the University of Missouri, Columbia, Mo.).In summary, there is a danger that reversed acellular dermis may not incorporate after primary tissue expander reconstruction. The lack of sufficient neovascularization may create a chronic foreign body reaction that presents as episodic cellulitis without concomitant seroma or abscess. This cause should be considered when such a constellation of symptoms presents in the setting of acellular dermis use in tissue expander breast reconstruction. Kamaldeep Heyer, M.D. Donald W. Buck, II, M.D. Caroline Kato, B.S. Seema A. Khan, M.D. Murad Alam, M.D. John Y. S. Kim, M.D. Division of Plastic and Reconstructive Surgery Northwestern University Feinberg School of Medicine Chicago, Ill. DISCLOSURE The authors have no conflicts of interest with regard to this research.