Types of melanoma: skin subtypes, eye (uveal) and mucosal melanoma

This page is general information, not medical advice. Your own doctor or care team is the right source for questions about your skin, diagnosis or treatment.

The word melanoma names a cancer of melanocytes, cells that make pigment. A longer name may identify where it began or describe a skin subtype. These names can make reports look more complicated, but they provide different kinds of information. The melanoma basics page explains the pigment cells and how melanoma differs from other skin cancers.

Skin melanoma and subtype names

The MedlinePlus melanoma encyclopedia entry describes the main skin melanoma subtypes and their typical appearances. It also explains that melanoma can begin on previously normal skin or develop in a mole. A mole is a cluster of pigment cells; its appearance alone is not enough to establish whether it is cancer.

Skin melanoma is also called cutaneous melanoma. The subtype words describe patterns such as an area spreading across the surface, a raised growth, or a growth at a particular site. The descriptions below are general reference descriptions. They do not identify a person's spot, and they do not replace the findings of a biopsy, a sample of tissue examined for signs of disease.

Superficial spreading melanoma

MedlinePlus describes superficial spreading melanoma as the most common skin subtype. It is usually flat, with an irregular shape and uneven color. The name concerns a pattern of spread across the skin. A reference description is not a requirement that every growth with this subtype must look exactly alike.

Wikipedia's reference on the subtype describes a pattern that can extend across the surface before growing into deeper tissue. It also describes growths arising in a pre-existing unusual mole or in previously normal skin. Superficial refers to that growth pattern; it should not be read as a statement that a melanoma cannot grow deeper.

Nodular melanoma

MedlinePlus describes nodular melanoma as commonly beginning as a raised area. It may have a dark blue-black or blue-red color, but some have no obvious pigment. A description based only on a dark mole therefore does not include every possible appearance.

Wikipedia's nodular melanoma reference distinguishes growth downward in thickness from growth across the skin. This helps explain why the height or width of a spot and the depth measured in tissue are different observations. Neither the subtype name nor the visible color tells a person the complete extent of a cancer.

Lentigo maligna melanoma

MedlinePlus describes lentigo maligna melanoma as usually occurring in older people on sun-damaged areas such as the face, neck, and arms. The area is often flat and tan with patches of brown. Again, these are typical descriptions, rather than an appearance checklist that establishes a diagnosis.

The related words lentigo maligna and lentigo maligna melanoma are not interchangeable. Wikipedia's reference describes lentigo maligna melanoma as melanoma arising from a lentigo maligna with cells invading beyond the epidermis, the outer skin layer. The longer name concerns that invasive finding. The meaning in an individual report belongs with the doctor interpreting the tissue and the rest of the clinical information.

Acral lentiginous melanoma

Wikipedia's acral lentiginous melanoma reference describes this subtype on palms, soles, and beneath fingernails or toenails, including areas not usually exposed to the sun. A mark beneath a nail may appear as a dark streak running lengthwise. These sites help explain the word acral in the subtype's name.

The reference describes a range of pigmentation, including some areas with little or no obvious color. It also notes that other skin or nail conditions can resemble this melanoma. A streak or spot is therefore a description to be assessed, rather than a diagnosis established by its location. The skin self-exam page explains the agency guidance about noticing changes, including the nails, palms, and soles.

Eye or uveal melanoma

The National Cancer Institute's eye melanoma summary explains that uveal melanoma begins in pigment-making cells in the uvea, a middle layer within the wall of the eye. Intraocular melanoma is another name used in that summary. These words concern where the melanoma begins, rather than a skin subtype.

The uvea includes the iris, ciliary body, and choroid. The iris is the colored part visible at the front of the eye. The ciliary body lies behind it and helps change the lens's shape for focusing. The choroid contains blood vessels that supply the eye. These parts explain the site names that may appear in information about eye melanoma.

The institute says that uveal melanoma may cause no early symptoms and is sometimes found during an eye examination. It describes tests that examine the eye and notes that a tissue biopsy is rarely needed to establish this diagnosis. That differs from the usual tissue diagnosis of melanoma on the skin. Skin self-exam descriptions should therefore not be used as an eye melanoma test.

Mucosal melanoma

Wikipedia's mucosal melanoma reference describes mucosal melanoma as melanoma in mucous membranes, the moist linings of certain body passages. It describes sites in the head and neck, the anorectal region, the vulva and vagina, and the urinary tract. Those names concern the location where the disease begins.

Because this form begins in a lining rather than in ordinary external skin, the descriptions of common skin subtypes do not explain its location. The reference also notes that melanomas of the vulva and vagina are often considered separately on the basis of clinical and tissue features. General naming information does not supply a personal prognosis or treatment plan.

Subtype, stage, and the pathology report

A pathology report records findings from tissue examination. A stage describes how much cancer is present and whether it has spread. These words can appear together because they answer different questions. The pathology report page explains how tumor thickness and other findings are described, without interpreting anyone's report.