Melanoma types are based on the way a sample of cells from a tumor looks under a microscope. These cells are collected during a biopsy or surgery. Determining the type is important because it can help your doctor understand where the melanoma is likely to grow and how quickly.
Four Main Types of Skin Melanoma
There are four main types of skin melanoma.
- Superficial spreading melanoma is the most common type of melanoma. It starts off by growing along the top layer of the skin. Eventually, it can penetrate deeper into the skin. Learn more about superficial spreading melanoma.
- Nodular melanoma is the second most common type of melanoma. It can be aggressive because it usually grows quickly. Its most common feature is a bump or node that rises above the skin’s surface and that is firm to the touch. Learn more about nodular melanoma.
- Lentigo maligna melanoma tends to develop on the face, scalp, or neck. It usually affects older people with very sun-damaged skin. Learn more about lentigo maligna melanoma.
- Acral lentiginous melanoma is a rare condition that affects people of all races and backgrounds. It is the most common form of melanoma in people of African and Asian descent. It can develop on the palms of the hands and soles of the feet as well as under the toenails and fingernails. Learn more about acral lentiginous melanoma.
Rare Skin Melanomas
Melanoma can also affect different parts of the eyes.
- Choroidal melanoma is the most common type of eye melanoma. It begins in the pigmented layer beneath the retina.
- Conjunctival melanoma refers to melanoma that begins in the clear conjunctiva, which covers the eye’s surface and the inside of the eyelids.
- Iris melanoma starts in the eye’s middle layer, which includes the colored iris surrounding the pupil.
Some melanomas can start in the tissues that line internal areas of the body. These cancers are called mucosal melanoma. They most often develop in the head and neck region, the anus, the vagina and vulva, and the gastrointestinal tract. Learn more about mucosal melanoma.