Melanoma of skin

**Definition:** A primary melanoma arising from atypical melanocytes in the skin. Precursor lesions include acquired and congenital melanocytic nevi, and dysplastic nevi. Several histologic variants have been recognised, including superficial spreading melanoma, acral lentiginous melanoma, nodular melanoma, and lentigo maligna melanoma.

**Exclusions:** - Melanoma of penis - Melanoma of vulva - Melanoma of anus or anal canal - Metastatic melanoma involving skin