Sun exposure and skin cancer, and the puzzle of cutaneous melanoma: A perspective on Fears et al. Mathematical models of age and ultraviolet effects on the incidence of skin cancer among whites in the United States. Am J Epidemiol. 1977; 105: 420-427.
This paper reviewed some hypothesised mechanisms of how skin cancers may develop. There was a landmark paper published in 1977 that first hypothesised that melanoma was caused by intermittent solar ultraviolet (UV) exposure (brief episodes of exposure to high-intensity UV) and that non-melanoma skin cancers were caused by progressive accumulation of sun exposure. Taking into account the knowledge since 1977, the authors suggested that while the intermittent sun exposure is still relevant, they elaborated on a new hypothesis called the dual pathway hypothesis (i.e. sun exposure early in life combined with intermittent sun exposure) for melanoma skin cancers.
In 1992 the International Agency for Research on Cancer (IARC) evaluated all the available evidence in relation to solar UV radiation and cancer. Based on “sufficient” evidence of carcinogenicity in humans and animals, IARC classified solar radiation as “carcinogenic to humans” (Class 1).
In 1994, the World Health Organization (WHO) conducted an in-depth review of the scientific literature concerning the effects of UV radiation exposure on human health and the environment.