But baring all when you’ve been covered up all year is a recipe for raising the risk of melanoma – a serious form of skin cancer that can spread rapidly. Far better to take it easy in the sun, a new study from the University of Leeds shows.
Doctors already know that people with a lot of moles on their skin have a greater risk of getting melanoma than people who hardly have any. The question is: what causes these moles – or ‘nevi’, as scientists call them – to appear? The answer lies in our genes and our behaviour, according to Professor Julia Newton-Bishop and colleagues.
The University of Leeds researchers studied the genetic make-up of around 1500 men and women with varying numbers of moles. They also asked the people taking part in the study how often they exposed their skin to the sun.
They found that people with certain genes on chromosomes 9 and 22 were more likely to have a lot of moles and that these moles tended to be bigger. A gene on chromosome 6 was linked to large moles but this gene did not increase the number of ‘nevi’.
But at the same time, people with a history of getting sunburn and who exposed their skin to the sun on holidays rather than moderately throughout the year were more likely to have a lot of moles too. Holiday sun exposure was also linked to large moles.
Men and women who said they spent a lot of time outdoors and often exposed their arms and legs to the elements regularly – but without burning – were less likely to have a lot of moles.
Taken together, these findings suggest that people who already have lots of moles – because of their genes – should be particularly careful not to get burned and would be well advised to adopt a ‘little and often’ approach.
“Like many illnesses, the reason we get skin cancer is partly due to our genes and partly due to our lifestyle or environment,” said University of Leeds Professor of Dermatology, Julia Newton-Bishop, who led the work: “What we want is for individuals to understand their own level of risk so they can modify their behaviour accordingly. This is all about knowing your own skin.”
She added: “It is no coincidence that women tend to have most moles on their lower legs. That’s because at the first sign of sun, the first thing many women do is try and brown that bit of their legs that is visible below the hemline as quickly as possible. This type of intense, rapid exposure is exactly what increases the risk of getting melanoma.”
Full details of the study will be published in the journal Cancer Epidemiology Biomarkers and Prevention.
The work was funded by the US National Institutes of Health.
For further information:
Paula Gould, University of Leeds press office: Tel 0113 343 8059, email firstname.lastname@example.org