What is melanoma?

Melanoma is the least common but most aggressive of the three most common types of skin cancer. Melanoma originates in the skin's melanocytes—the cells that produce pigment, or melanin. Melanoma typically appears in or around a mole, but it may also develop on clear skin. It may be a flat, brown, black or tan spot or a raised bump. Unlike a noncancerous mole, melanoma often is irregularly shaped.

Characteristics of melanomas include:

  • Melanomas are black, irregular, asymmetric, growing, and have a rough border. They are especially common on women’s legs—it’s the second most common cancer in women ages twenty to twenty-nine. Risk rises if a parent or sibling has had it.
  • Among African-Americans and some other ethnic groups, most likely to appear in non-sun-exposed areas: on the palms, soles of the feet, mucous membranes, and under fingernails and toenails. (Bob Marley died of melanoma that started on the sole of his foot and spread to his brain.) Melanomas can also form in the eye and the gut.
  • If it’s detected and treated early, the five-year survival rate is 99 percent. If it’s allowed to spread to other places in the body, the survival rate decreases rapidly.

From The Mind-Beauty Connection: 9 Days to Less Stress, Gorgeous Skin, and a Whole New You by Amy Wechsler.


Melanocytes are found throughout the lower part of the epidermis. They make melanin, the pigment that gives skin its natural color. When skin is exposed to the sun, melanocytes make more pigment, causing the skin to tan, or darken.

The skin is the body's largest organ. It protects against heat, sunlight, injury, and infection. The skin has 2 main layers: the epidermis (upper or outer layer) and the dermis (lower or inner layer).

When melanoma starts in the skin, the disease is called cutaneous melanoma. This PDQ summary is about cutaneous (skin) melanoma. Melanoma may also occur in the eye and is called intraocular or ocular melanoma.

There are 3 types of skin cancer:

Melanoma Basal cell skin cancer Squamous cell skin cancer

Melanoma is more aggressive than basal cell skin cancer or squamous cell skin cancer.

This answer is based on source information from the National Cancer Institute.

Dr. Doris Day, MD
Dermatologist (Skin Specialist)

This is the third most common form of skin cancer, and the most deadly. Fortunately it is also the least common type of skin cancer we see, accounting for 4 percent of all skin cancers. The incidence of melanoma seems to be due mostly to genetic factors and multiple sunburns, especially before the age of 18, although there are no definitive studies that directly link melanoma with sun exposure. Melanoma looks like a brown to brownish black spot that can be flat or raised. Sometimes it can ulcerate and bleed. It occurs more commonly on sun-exposed parts of the body, but can occur anywhere including the scalp, palms or soles, and even on the genitals, or in the parts of the eyes.

Melanoma most commonly occurs in a mole that is already present, but can also occur on previously normal-appearing skin. This kind of skin cancer is capable of spreading internally and can be fatal if not caught early. One person dies in the United States every hour from malignant melanoma.

Dr. Arthur W. Perry, MD
Cosmetic Surgeon

Melanomas are the most ominous type of skin cancer. They can grow spontaneously or can arise from moles. They should be surgically removed without delay. The prognosis is largely related to the thickness: thin melanomas are readily curable; intermediate-thickness melanomas may require removal of the local lymph nodes; thick melanomas can spread throughout the body and have a very poor prognosis. Melanomas usually are pigmented, but some are flesh colored.

Straight Talk about Cosmetic Surgery (Yale University Press Health & Wellness)

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.