Face Transplantation

Introduction

The notion of drastically improving the treatment of catastrophic facial injuries, regardless of the cause, has motivated surgeons to pursue the development of facial transplantation in addition to other types of vascularized composite allotransplantation (VCA) over the past few decades. Historically, the reconstruction of such daunting facial defects has been demanding, often requiring numerous procedures and often yielding less than ideal results. Conventional techniques have been largely inadequate to restore facial aesthetics and function in these severe injuries, while the reconstruction of anatomically and functionally complex facial structures such as the nose, lips, and eyelids has been especially disappointing. Despite significant effort and treatment, these patients are often left with lifelong functional and aesthetic handicaps.

The first facial transplantation in the world took place in Amiens, France in 2005. In the decade since, there have been nearly 30 reported full or partial face transplants performed in over a half dozen countries and several more that have not yet even been reported. The first patient was a 38-year-old woman who sustained severe injuries to the lips, nose, and cheek from a dog bite. The early results from this procedure were remarkable, in that it provided the entire world with a medical breakthrough and gave hope to patients with facial defects considered “unreconstructable” by conventional methods. Since then, several other facial transplantations have been performed and the encouraging outcomes of these cases have also demonstrated the amazing potential to restore facial aesthetics and function that was previously impossible with traditional reconstructive techniques. However, the enthusiastic outlook toward facial transplantation among the medical community has recently become more guarded, given that three of the transplant patients have died. The first patient died of unknown causes in China, secondary to his refusal to take immunosuppressive medications, while the second patient was a severely burned patient, who received a simultaneous bilateral upper extremity and facial transplantation and died of sepsis 1 month after his procedure. The third confirmed death after facial transplantation occurred in an HIV-positive patient as a result of tumor recurrence after a prior cancer resection. In addition to these tragic deaths, several minor complications have been reported, including infections with opportunistic organisms and steroid-induced diabetes mellitus. Despite these issues, the fact that the long-term outcomes of facial transplantation are unknown and the fact that this procedure is still largely considered experimental, there remains an excitement among reconstructive surgeons and patients alike about this powerful new technique.

The practice of organ transplantation is associated with a variety of ethical issues, including the limited availability of donors, the risk of rejection, and the importance of informed consent for both donors and recipients alike. On top of these issues, there arises an additional set of new ethical dilemmas for facial transplantation related to the potential transfer of a person's appearance or identity as well as the risk–benefit ratio of the procedure. Concerns regarding self-identity are based on the recognized role of facial features in perceptions of identity and self, as well as our dealings with others. Critics of facial transplantation might argue that a disruption in self-recognition may lead to regret, depression, and potentially even life crises. On the other hand, a loss of self-recognition is likely to already be present in candidates for facial transplantation due to their pre-existing facial disfiguration. Additionally, facial transplantation may help candidate patients further regain their lost sense of identity, by giving them the ability to communicate emotions through facial expressions, which may in fact be more important to a sense of identity than facial contours and features. The early results from the first few cases of facial transplantation performed demonstrate that transplant recipients do in fact regain much of their social capacity and even accept the allograft as part of their own body.

Unlike solid organ transplantation, facial transplantation is mainly performed in patients with an otherwise normal life expectancy. However, the required immunosuppressive therapy is likely to shorten life expectancy because of untoward side effects. Furthermore, rejection and loss of the allo­graft would require replacement with a new allograft or reconstruction by conventional techniques, with likely inferior results. When balancing the risks and benefits of facial transplantation, the social stigmatization experienced by those patients with severe facial disfigurement must be considered as an acceptable facial appearance is important for normal social interactions. As a result, patients with severe deformities have been willing to accept the risks given the potential of the procedure to vastly enhance their quality of life.

Facial transplantation is an extraordinarily complex and resource-demanding undertaking, with the potential to change a patient's life for the better after a disfiguring accident. A multidisciplinary team is necessary to address all the different aspects of the preparation, procedure, and follow-up. Potential candidates for facial transplantation need to undergo vigorous physical and psychological testing preoperatively. A diverse surgical team is also needed, with expertise in head and neck reconstruction, microsurgery, craniofacial surgery, and transplant surgery. Close follow-up with a battery of tests, as well as daily therapy sessions are needed postoperatively. This chapter aims to shed some light on the exciting and expanding new field of facial transplantation.

Immune Suppression

As with any type of allotransplantation, the composite tissue allograft will be recognized as foreign tissue by the recipient's immune system, which will lead to immunologic rejection. At the time of writing, this can only be prevented by lifelong immunosuppressive therapy, which carries with it significant risks and side effects. Compared with the transplantation of a solid organ, such as a kidney or liver, which could be considered lifesaving, the risks and side effects of these medications must be weighed seriously against the non-lifesaving nature of facial transplantation procedures. Once the surgical feasibility was established, the immunologic problem has become the main obstacle against VCA of all types. As a result, the continuous need for the development of new and improved immunosuppressive therapies is of paramount importance to VCA.

Allograft rejection is the process where the transplanted tissues are attacked by the recipient's immune system after it has been recognized as foreign and therefore potentially harmful. Rejection is caused by a genetic incompatibility between components of the recipient and donor tissues. These incompatible components are known as antigens. It is these antigens, along with antigen presenting cells (APCs) and T-cells, that are the three major players in allograft rejection. Less commonly, other tissues in the recipient's body may be attacked by components of the donor's immune system that have been harbored in the allograft. This is known as graft-versus-host disease (GVHD).

Immunosuppressive therapy typically begins immediately after surgery (induction therapy) to prevent the rejection of transplanted composite tissues and must continue (maintenance therapy) under close monitoring, as long as the graft remains viable. Induction therapy is essential to delay the onset of acute rejection while allowing for maintenance agents to reach their therapeutic levels. Table 64.1 outlines the main agents used for both induction and maintenance therapy at our institution. Maintenance therapy is typically a tri-agent therapy. Rescue therapy is provided to patients during episodes of acute rejection and initially starts with corticosteroid boluses. If this is unsuccessful, the antibody agents used for induction therapy can be used in addition. In contrast to solid organ transplantation, topical forms of some agents such as corticosteroids or tacrolimus, can be used as rescue agents in face transplantation.

Indications

In the future, face transplantation may become the treatment of choice for patients with considerable functional and social impairment, as a result of severe facial disfigurement. These disfigurements often are very large, involving more than 25% of the surface area of the face and usually involve more than just one of the aesthetic subunits of the face. The detailed and intricate anatomic characteristics of the structures destroyed in these disfiguring incidents are often impossible to completely restore with traditional reconstructive techniques. As a result, the transplant of a facial allograft presents surgeons with a unique opportunity to restore not only the form but also the function of these damaged structures to patients.

Severe facial disfigurement can be the result of a wide array of causes. Prominent causes include, but are not limited to trauma, burns, congenital defects, infections, and cancer. For example, the first two face transplants ever performed were to correct traumatic defects caused by the violent attacks of a dog and a bear. Face transplant operations have been performed in the United States for disfigurements caused by high-voltage electrical burns, chemical burns, animal attacks, as well as for a traumatic defect caused by a shotgun blast. Additionally, face transplantation has been performed on two patients to correct defects resultant from neurofibromatosis. As indicated by these few cases, there is a particular set of challenges and difficulties associated with each patient and the reconstruction of their unique defect based on its cause.