So-called ‘normal looking’ skin can still harbour sun-damaged DNA mutations that can contribute to the development of skin cancer, according to the results of a University of Queensland study published in Science Advances.
The researchers from the Frazer Institute Dermatology Research Centre took samples of this normal looking skin, which was relatively free of visible freckles or blemishes, from the forearms of 37 skin cancer patients. After analysis, a high number of mutations were identified.
“They had an average of four to five times more mutations in normal-looking skin compared to similar studies overseas,” said lead author and PhD candidate Ho Yi Wong in a press release. “The higher mutation levels are likely due to Australia having two to four times higher levels of ultraviolet light than the United Kingdom and Europe.”
Then, the researchers matched people of the same age and sex who had a different number of skin cancers.
“One group had many skin cancers and the other group had few to none in the past five years,” Wong said. “We found a 45 per cent difference between the groups, with a much larger number of mutations on the forearms of those with more skin cancers.”
According to senior author Professor Kiarash Khosrotehrani, the study findings help to explain why people with a single skin cancer have a much higher chance of developing other cancers in the same area of the body.
“The findings also suggest that if we reduce mutation levels in normal-looking skin then we could reduce the risk of new skin cancers,” Professor Khosrotehrani said in the release.
Ablative therapy such as lasers and dermabrasion can help reduce skin mutations, but these preventive treatments are difficult and expensive to implement on a large scale, he noted.
“Our next step is to explore therapies that can reduce the load of skin mutations,” Professor Khosrotehrani said.