Solar ultraviolet exposure and mortality from skin tumors.

Solar UV radiation (UVR) exposure is clearly associated with increased mortality from nonmelanoma skin cancer--usually squamous cell carcinoma. However, the association with cutaneous melanoma is unclear from the evidence in ecologic studies and several analytic studies have conflicting results regarding the effect of high levels of intermittent UV exposure prior to diagnosis on mortality. Understanding this conundrum is critical to present coherent public health messages and to improve the mortality rates from melanoma.