The relationship of sun exposure and solar elastosis to skin cancer in a high risk population.

The significance of chronic sun exposure in the pathogenesis of skin cancers squamous cell carcinoma (SCC). basal cell carcinoma (BCC) and melanoma was morphologically assessed. Histological sections of 223 consecutive skin cancers were reviewed, these were stained with aldehyde fuchsin and the degree of associated solar elastosis estimated. The anatomic distribution of SCC and BCC and the SCC:BCC ratio were significantly different in the Irish population studied when compared to other major series. It was found that a significant proportion of SCCs and BCCs were not related to chronic sun exposure. As expected, only melanomas arising in lentigo maligna were associated with long-term irradiation. It is proposed that other environmental agents and genetic factors may also contribute to the high incidence of skin cancer in Ireland.