ESOT 2013 Report – Fantastic transplantations or transplantation fantasies? The new frontiers of abdominal organ transplantation

Andreas Tzakis , Weston, USA  – Advances in vascular reconstruction techniques in recent years has transformed the concept of multi-visceral or cluster transplantations from the very forefront of surgery to routine procedures with excellent long-term outcomes. Dr Andreas Tzakis from the Cleveland Clinic in Florida reviewed the most up to date survival data from different cluster transplant derivatives, including the more pioneering concept of abdominal wall surgery. The second half of Dr Tzakis’ talk was devoted to uterus transplantations, a highly experimental concept which has only recently progressed into clinical development.

 

The concept of multi-visceral transplantation was first described in the 1960s; after several attempts, the first long-term survivor of multi-visceral transplantation was operated on in 1989 and survived for a year. Since then, long-term survival has improved steadily – at Dr Tzakis’ own centre in Miami, more than one third of the paediatric patients and one quarter of adult patients undergoing multi-visceral transplantation are still alive 17 years post transplantation.  The vast majority of patients – around 90% – are able to return to normal nutrition and regain normal body mass index (BMI). Although attrition rates remain considerable both in terms of patient and graft survival, especially for multivisceral transplantations that do not include the liver, and many patients develop neuropsychiatric complications such as depression and cognitive impairment, and developmental delays in children, the vast majority of patients are able to complete their education and find employment.

 

The success of cluster transplantations has paved the way for other forms of abdominal transplantation. Key advantages with performing composite abdominal transplantations include the need for only two vascular anastomoses – the aorta and the inferior vena cava – and retaining the protective effect of the liver. Three-dimensional fit may be a challenge, and Dr Tzakis recommended that the donor should be smaller than the recipient if possible. Procedures such as en-bloc liver-kidney transplantations has proved an excellent procedure in children with congenital hepatic fibrosis and autosomal recessive polycystic kidney disease, and composite liver, kidney and pancreas transplantations provide a treatment for Wolcott-Rallison syndrome which is the most common cause of diabetes in neonates.

 

Abdominal wall transplantation is a highly specialised derivative of cluster transplantation which was first performed in 2001. The procedure involves anastomosing a combination of epigastric and iliac vessels into the lower abdomen and can be used to cover almost any abdominal defect, in most cases with excellent functional and cosmetic outcomes. Recent developments of this procedure include using extraperitoneal vessels to avoid having to go behind the multivisceral graft; and remote revascularisation of the abdominal wall graft via the forearm.

 

Uterus transplantation has been proposed as an option for overcoming uterine infertility, which currently affects around 3-5% of women in the developed world. Uterus transplantation is regarded as a life-enhancing rather than life-saving procedure, and unlike other forms of transplantation it is ephemeral in nature – it is not intended to last for the lifetime of the recipient and once the graft has served its purpose, immunosuppressive therapy can be withdrawn and the graft either rejected or removed.

 

To date, successful uterine transplantations with subsequent pregnancies have been achieved in sheep and non-human primates – the clinical experience in humans is as yet extremely limited. A clinical trial was initiated last year at the University of Gothenburg in Sweden, a world-leading centre in this field. A total of nine women have received uterus transplantations from live donors at this centre since September 2012; under the protocol, in vitro fertilisation will take place at a minimum of 12 months after transplantation. Although it is far too early to predict the outcome of this trial, Dr Tzakis is hopeful that just like in the case of multivisceral transplants, this may indeed prove to be a fantastic step forward, rather than merely a fantasy.