There are four main types of melanoma of the skin:

• Superficial spreading melanoma

This is the most common. In women, the most common part of the body for this to develop is the legs. In men, melanoma most often occurs on the chest and back. Melanoma cells most often grow slowly at first and spread throughout the entire skin surface.

• Nodular melanoma

This is the second most common type. It can grow more rapidly than other melanomas and is normally found on the chest, back, head, and neck.

• Lentigo maligna melanoma

This is seen in older people on areas of skin that have had high sun exposure over many years. It often develops on the skin and neck. It begins with a slow-growing precancerous condition called lentigo maligna or Hutchinson's melanoma, which looks like a spot on the skin.

• Acral melanoma

This type is more uncommon. It is generally found on the palms of the hands, the bottoms of the feet, or below the nails. It is more common among people with dark skin, and it is not believed to be related to sun exposure.

On rare occasions, melanoma can start in parts other than the skin, such as the eye (ocular melanoma) or on tissues that line internal areas of the body such as the anus or the rectum (anorectal melanoma), nose, mouth, lung, and other areas.