January 24 1999 BRITAIN
First tongue transplant will restore speech
by Steve Farrar
and Dipesh Gadher
SCIENTISTS are planning the world's first tongue transplant to restore the ability of oral cancer victims to speak and eat.
The operation would be exceptionally challenging because the network of nerve fibres, blood vessels and muscle tissue within the tongue is among the most dense and most complex in the body.
Mastering the techniques would, however, bring surgeons significantly closer to achieving full face transplants to help burns victims. The microsurgery needed to reconnect the facial nerves would be similar to that developed in tongue transplants. Dr Bruce Haughey, who is leading the research at the University of Washington in St Louis, Missouri, said: "We have proven it is technically possible through animal experiments and we are progressing steadily towards the goal of transposing this to humans."
The tongue is a much bigger organ than commonly realised, with muscular roots extending to the base of the jaw. It is packed with nerves and blood vessels to help it to perform complex functions such as speaking, tasting and manipulating food so that it is swallowed and does not block the airways.
These roles mean, however, that the tongue and mouth are exposed to a wider range of foreign substances than most organs and so are prone to infection and other disease. The increasing use of tobacco and alcohol by young people are believed to be the main causes of the increase in oral cancer. Until now the only treatments have been surgery and radiation. In the worst cases patients have the entire tongue amputated.
Victims can be left severely disabled, as happened to John Diamond, a columnist with The Times. Last week Diamond said: "One is never conscious of the extent to which the tongue is the thing which gets the food from the front of the mouth to the back until it goes. Without it the food just hangs around in the mouth."
Haughey's techniques give hope that some sufferers could regain such abilities. He has already carried out tongue transplants on dogs. Last week he said he was ready to use the technique on humans.
The likelihood is, however, that patients undergoing such a transplant would already have had all or part of their tongues removed in previous operations. There would probably also be other damage from the radiotherapy often used to treat this cancer.
For transplantation the first step would be to remove as much of the remaining tongue as necessary to expose undamaged tissue. Next, a tongue from a cadaver would be trimmed to fit and attached to the patient's "stump". Delicate microsurgery would connect the nerves, blood vessels and muscle tissue. Finally, stitches would be inserted to bind the tongue firmly into the back of the mouth.
Iain Hutchison, a consultant oral and facial surgeon at St Bartholomew's hospital, central London, welcomed the American developments. He said he rebuilds oral cancer patients' tongues using muscle tissue from the back, abdomen or arm, but the results are often unsatisfactory. "You can rebuild most of the tongue in this way but it won't move in a co-ordinated fashion," he said.
In Britain about 1,400 people die from oral cancer every year. Hutchison and other experts predict this will rise to "epidemic" proportions in the next 30 years because of the surging popularity of smoking in youngsters. The incidence is particularly high in Scotland, especially Glasgow, and industrial areas of northern England where smoking and drinking levels are high.
Agnes McKee, a 42-year-old administrator from east London, was diagnosed with tongue cancer last month and had 90% of her tongue removed. The tongue was rebuilt with tissue from her back but she has lost some of her speech and the ability to cope properly with solid foods. "I would definitely have considered a transplant," she said.
The tongue graft is just the latest of many transplant surgery advances. In 1998 American surgeons carried out the first voice box transplant on a man whose throat was damaged when he rode his motorbike into a piece of cheesewire stretched between two trees by vandals. Another group of surgeons successfully transplanted a scalp onto a cancer victim who had a tumour removed from the forehead. A third team in France gave a man a new hand.
A serious complication of such operations - which would also affect tongue transplant recipients - is that patients face a lifetime of taking drugs to prevent their bodies rejecting the replacement.
Some surgeons believe that advanced transplant techniques will soon overcome even this difficulty. James Frame, a consultant plastic surgeon at St Andrew's Centre for Plastic Surgery and Burns in Chelmsford, Essex, said: "In the long term the answer is to grow transplant organs in laboratories. That will overcome rejection problems."
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