Acetal melanoma is not related to sun, superficial is related to sunburns, lentigo is to chronic sun exposure, what is nodular related to?

Time growth: The pattern of growth of melanoma is defined by the thickness of the lesion with those defined by Breslow of more than 1.5 mm thick having a greater possibility of spreading. With time the flat, thin appearance changes and the melanoma grows thicker to take on a nodular appearance. Later, this nodular lesion takes on an ulcerating picture wherein the prognosis is far poorer.

UV radiation: Exposure to UV radiation from the sun is the main cause of all types of skin cancers and melanoma. There also is a genetic component to melanoma as we see increased risk in those with a family history. Remember to limit your exposure to UV radiation. Wear a sunscreen with an SPF of at least 30 and try to cover up as much as possible.