ABSTRACT
Skin cancers, both nonmelanoma and melanoma, are being influenced by geneti-
cally determined host factors and by exposure to an environmental carcinogen,
solar ultraviolet (UV) radiation. However, while squamous cell carcinomas
(SCCs) of the skin and solar keratoses (an actinic precursor skin lesion) are
clearly induced by chronic and cumulative exposure of body surfaces to sunlight,
substantial proportions of basal cell carcinomas (BCCs) and melanomas are
associated with intermittent exposure of usually covered body parts, such as
recreative sun exposure during holidays, more especially during childhood,
rather than with chronic sun exposure (1). Furthermore, while wavelengths
responsible for the induction of SCC lie within the UVB range of the UV spec-
trum, wavelengths responsible for the induction of BCC and melanoma are not
yet fully identified and may involve UVB as well as UVA (2).
