Risk factors for melanoma development

Melanoma incidence has risen over the last 30 years; however, whether this increase is entirely genuine or caused, in part, by increased screening, needs to be addressed. A large number of nevi is the strongest risk factor for melanoma across all Caucasian populations. Number of nevi is heritable with 60% of the variation in their number attributed to additive genetic effects. Fair hair and skin is also a heritable risk factor but the magnitude of the risk is much smaller than nevi. There are different ‘at-risk’ phenotypes leading to melanoma: high number of nevi or alternatively sun damage with solar keratoses, and these two phenotypes are usually mutually exclusive. This suggests different pathways leading to melanoma. Sun exposure is linked to melanoma with an increased melanoma incidence with decreasing latitude. However, this association is very complex and is not dose dependent. Similar to all cancers, melanoma can cluster in families. Between 20 and 40% of melanoma-prone families have mutations in ...