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Prevention
and Management of Skin Problems
Please note, this page is a summary of the full conference speech (click here for the full transcript - including photographs).
Tony Chu
Head of the Section of Dermatology at the Imperial College of Science, Technology and Medicine, Senior Lecturer and Honorary Consultant Dermatologist at the Hammersmith Hospital and Ealing Hospital.
"And that's exactly what he did for the next five years. He went to Thailand, he went to Spain, and he sat and basked in the sun. And that of course was the worst possible thing he could do," said Dr Chu.
"I feel very strongly that all transplant units should have a package that they give to the patient telling them exactly what they should and should not do."
The real problem was with warts, caused by a virus called human papilloma virus. They were very common in childhood, and they recurred throughout life, because immunity to the wart virus was short-lived. But the human papilloma virus was implicated in cervical cancer.
Transplant patients tended to develop warts four or five years post transplant, and at the Hammersmith Hospital he routinely reviewed all patients five years after their transplant and thereafter. There was a real risk that these warts developed into squamous cell carcinomas after sun exposure.
Warts were treated usually with cryotherapy, which used a very cold solution of liquid nitrogen down to -180 degrees to induce a thermal burn in the skin. A new cream called Imiquinod developed by an American company called 3M and licensed in Britain for genital warts enhanced the immune system locally to cope with a viral infection. At the Hammersmith they were just about to embark on a trial looking at Imiquinod.
In the unit at the Hammersmith, if you had had a skin cancer it would be taken as a reason to refuse a second transplant. So it was very important to protect against them.
In the normal population, the commonest type of skin cancer was a basal cell carcinoma which could usually be treated very easily. The ratio of basal to squamous cell carcinomas was 10: 1. In the transplant patients, squamous cell carcinomas were ten times as common as basal cell carcinomas. Squamous cell carcinomas were metastatic - they didn't just grow locally, they spread to the lymph glands and eventually went through to other parts of the body, and once they've actually spread beyond the skin then there was very little you could do about it.
"Melanoma is probably the worst cancer we see in the skin," said Dr Chu.
"It's increased in transplant patients, it's a very aggressive skin cancer, it may arise from a pre-existing mole, or it may come up in normal skin. And in the immunosuppressed patient it is often very aggressive."
Generally the major factor in the development of skin cancer was the sun. Ultra-violet light was divided into three different bands- UVC, UVB and UVA. UVB was probably the most important as far as developing skin cancer went. UVC was the most carcinogenic, but it did not get down to the earth's surface because of the ozone layer. A lot of UVB was filtered out, though some still penetrated down to sea level. UVA still got through and it got down even to the Dead Sea level.
Basal cell carcinomas were the commonest cancers in the Caucasian populations, with sun exposure as the major cause. Common sites were on the face and the trunk, but they were not metastatic, they didn't spread round the body. They were called rodent ulcers because they looked as if a rat has been chewing at you.
Melanoma was the third most common skin cancer, but in young women it was the second most common skin cancer. The major cause was severe intermittent sun exposure, and it had a very high metastatic potential. Thirty per cent arose from a pre-existing mole, which became asymmetric, irregular in its shape and colour.
"At this stage, if you remove it, that's totally curative," said Dr Chu.
"To avoid these problems, certainly avoid the midday sun. Use photo-protective clothing and hats, and use high factor sun block."
Certainly from the end of March till the end of September, you needed a high factor sunblock, even when it was raining. Even if you were sitting in the shade you were not protected. Dr Chu recommended that you remained indoors between 11am and two o'clock.
"If you have a bit of clothing that you think is going to protect you, hold it up against the light. If you can see light through it, then it's not going to give you much protection," he said.
"Essentially the finer the weave the greater the protection. So silk is the best and silk is rather nice to use."
Women who wore stockings had to have sunblock underneath. Panama hats were not suitable because they had holes in them. Instead he recommended a cotton hat with a broad brim.
Sunscreens came in a wide and confusing range. There were two types - the reflectants, which just reflected ultra-violet light away from the skin, and because of their nature they tended to be white. The absorbent ones absorbed ultra-violet B and the chemicals rendered the energy into minor quantities of heat. Dr Chu recommended the use of high factor sunblocks, SPF 60, right through the year,
Azathioprine, ciclosporin and tacrolimus all had the same effect on the skin, so being on one of those did not help.
"But one of my patients - and this was a particularly problematic patient, in that we were removing a squamous carcinoma roughly every six weeks from his body - he was changed to mycophenolate mofetil, and since then he's developed no further tumours, said Dr Chu.
"He still has the warts, and we still freeze those, but he's developed no further tumours. So I think that the search for newer immunosuppressants that could be as effective in the transplant but with fewer long-term side effects is still there and we need to push that further."
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Please note, this page is a summary of the full conference speech (click here for the full transcript - including photographs).
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