Comparison of the time and latitude trends of melanoma incidence in anorectal region and perianal skin with those of cutaneous malignant melanoma in Norway

Abstract

Background Melanoma incidence is increasing in many parts of the world. The main environmental risk factor is

Epidemiology of Anorectal Melanoma in the United States

“…A more recent Norwegian study of anorectal melanoma cases from the Cancer Registry of Norway from 1966 to 2007 did not demonstrate a significant association between latitude and anorectal melanoma. 5 These analyses of latitude used the location of diagnosis, which may or may not represent lifetime residency in an area and thus lifetime ultraviolet radiation (UVR) exposure. Location of diagnosis is not a good proxy for lifetime UVR exposure and cannot be properly analyzed as such.…”

“…4 One prior US study noted that the incidence of anorectal melanoma was associated with more northern latitudes although a subsequent study in Norway did not confirm this association. 5,6 Cutaneous melanoma can affect all ages, with a higher incidence in women than men under the age of 40 years, but a higher incidence in men than women over the age of 40 years. 7,8 Prior studies of anorectal melanoma consistently demonstrated that the incidence of anorectal melanoma increases with age, with reported mean ages ranging from 68 years to 72 years, and that the incidence in women is 1.6 to 2.3 times higher than in men.…”

The relationship between UV exposure and incidence of skin cancer

“…It is well known that there are other skin carcinogens than UV exposure (for instance, chemicals and X-rays) (41). This can convincingly be seen from the fact that all three forms of skin cancer sometimes arise, although with a low RTD, on body localizations rarely or never reached by the sun (42,43).…”

Solar UV exposure in construction workers in Valencia, Spain

“…Some recent studies show that the incidence of melanoma is related to both altitude and latitude (Aceituno et al 2011;Boniol et al 2005;Chang et al, 2009;de Vries et al, 2004;Downs et al, 2011;Micu et al, 2011;Moehrle and Garbe, 1999;Pfeifer et al, 2006). Due to its geographical situation, for most of the year the Valencia Region (Spain) receives large doses of UVR.…”