EPIDEMIOLOGY OF SOLAR KERATOSES

Solar keratoses (SKs) or actinic keratoses are common dysplastic epide rmal lesions which occur in pale-skinned individuals who are chronical ly exposed to intense sunlight. Together with basal cell carcinomas an d squamous cell carcinomas, they constitute a major public health prob lem in such individuals. Reported SK prevalence rates range from 11 to 25% in various northern hemisphere populations, and amongst Australia n adults the range is from 40 to 60%. In the only study to date report ing SK incidence data, 60% of subjects aged 40 years and over with SKs at baseline developed new lesions during 12 months of follow-up, comp ared with only 19% of those who were lesion-free on the first examinat ion. Because existing epidemiological data on SKs are sparse, very lit tle is known of their natural history, their role in carcinogenesis, o r their preventability. In this review, current knowledge about the ae tiology, diagnosis, and occurrence of SKs is discussed, as is the need for prospective studies in unselected communities. With accurate base line data, public health authorities should be in a better position to determine the best preventive strategies, and to evaluate the effecti veness of these programmes.