Often, this disease evolves from a precursor lesion, usually a dysplastic nevus. Otherwise it arises in previously normal skin. A prolonged radial growth phase, where the lesion remains thin, may eventually be followed by a vertical growth phase where the lesion becomes thick and nodular. As the risk of spread varies with the thickness, early<unk>  is more frequently cured than late nodular<unk> .
Superficial spreading melanoma
Acral lentiginous melanoma
Lentigo maligna melanoma
Polypoid melanoma
Pseudomelanoma
Nodular melanoma
Animal-type melanoma
Desmoplastic melanoma