The epidemiology of UV induced skin cancer

There is persuasive evidence that each of the three main types of skin canc er, basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and melanoma, is caused by sun exposure. The incidence rate of each is higher in fairer skinned, sun-sensitive rather than darker skinned, less sun-sensitive peopl ed risk increases with increasing ambient solar radiation; the highest dens ities are on the most sun exposed parts of the body and the lowest on the l east exposed; and they are associated in individuals with total (mainly SCC ), occupational (mainly SCC) and non-occupational or recreational sun expos ure (mainly melanoma and BCC) and a history of sunburn and presence of beni gn sun damage in the skin. That UV radiation specifically causes these skin cancers depends on indirect inferences from the action spectrum of solar r adiation for skin cancer from studies in animals and the action spectrum fo r dipyrimidine dimers and evidence that presumed causative mutations for sk in cancer arise most commonly at dipyrimidine sites. Sun protection is esse ntial if skin cancer incidence is to be reduced. The epidemiological data s uggest that in implementing sun protection an increase in intermittency of exposure should be avoided, that sun protection will have the greatest impa ct if achieved as early as possible in life and that it will probably have an impact later in life, especially in those who had high childhood exposur e to solar radiation. (C) 2001 Elsevier Science B.V. All rights reserved.