As you might expect, this melanoma travels along the top layer of the skin for a fairly long time before penetrating more deeply. The first sign is the appearance of a flat or slightly raised discolored patch that has irregular borders and is somewhat geometrical in form. The color varies, and you may see areas of tan, brown, black, red, blue, or white. Sometimes an older mole will change in these ways, or a new one will arise. The melanoma can be seen almost anywhere on the body, but is most likely to occur on the trunk in men, the legs in women, and the upper back in both.
Most melanomas found in the young are of the superficial spreading type.
Lentigo maligna is similar to the superficial spreading type, as it also remains close to the skin surface for quite a while, and usually appears as a flat or mildly elevated mottled tan, brown, or dark brown discoloration. This type of in situ melanoma is found most often in the elderly, arising on chronically sun-exposed, damaged skin on the face, ears, arms, and upper trunk. Lentigo maligna is the most common form of melanoma in Hawaii. Lentigo maligna melanoma is the invasive form. The third type of melanoma, acral lentiginous melanoma , also spreads superficially before penetrating more deeply.