Melanoma

What is melanoma?

Melanoma is the most severe form of skin cancer. It occurs when cancer cells develop in the cells that produce melanin (melanocytes). Melanin is the pigment that gives skin its color. Melanoma can spread to other parts of the body, like the eyes and other internal organs. Melanoma is most common in adults, but it can appear in children. In men, melanoma is often found on the area from the shoulders to the hips, or the head and neck. In women, it most often forms on the arms and legs. It is much more common in people with lighter skin than people with darker skin. The number of new cases has been increasing over the last three decades.

What are the symptoms of melanoma?

Melanomas can develop anywhere on the body, but most often develop in areas that get a lot of exposure to the sun. Common symptoms include:

New, different looking spot on the skin that changes size, shape and/or color
Changes in an existing mole
New moles growing near an existing mole
Changes in the skin’s color

Normal moles are usually one color (like brown, black or tan) with a distinct border that separates the mole from the surrounding skin. They are round and usually smaller than 1/4 inch. The average amount of moles in a healthy person is between 10 and 45, most of which develop by age 50. There is a guide to help identify unusual moles that may indicate melanomas, called ABCDE:

A: Asymmetrical shape: one half of the mole’s shape doesn’t match the olther.
B: Irregular border: the mole has irregular, ragged or notched borders.
C: Changes in color: the mole has many colors.
D: Diameter: the mole is larger than 1/4 inch (which is about the size of a pencil eraser).
E: Evolving: the mole changes over time—growing bigger, changing color, itching, or bleeding

Some melanomas develop in areas of the body that don’t have much exposure to the sun, like under a nail, or in the eyes, mouth, vagina, urinary tract, or digestive tract. People with darker skin are more likely to develop melanomas in these hidden areas.

What causes melanoma?

Normal, healthy cells grow at a steady rate, and die at a set time. However, sometimes healthy cells develop abnormalities; they grow and multiply at an out of control rate, and take much longer to die. They accumulate and form melanomas. The exact cause of all melanomas isn’t clear. However, a major risk factor is exposure to ultraviolet (UV) radiation from sunlight, tanning lamps, and tanning beds. Limiting UV radiation exposure can help reduce one’s risk of melanoma. Other risk factors include: having a fair complexion, having lots of moles, and having a family history of unusual moles/melanoma.

How is melanoma diagnosed?

Melanoma is diagnosed using the following procedures:

Skin cancer screening and exams
Skin biopsy

After diagnosis, various imaging tests (CT scans, MRIs, X-rays) and other exams are used to find out if the cancer cells have spread to other parts of the body. This is called staging.

How are melanoma stages determined?

Doctors use the information obtained during diagnosis to assign a patient’s cancer a stage to help create the patient’s treatment plan. They do this by determining the thickness of the melanoma, seeing if the melanoma has spread to other parts of the body, checking for ulceration (a breakdown of the skin over the melanoma), and examining biopsy results. The basic stages are:

Stage I: The melanoma is small and hasn’t spread
Stage II: The melanoma has gotten bigger
Stage III: The melanoma may be any size, but it has spread to the lymph nodes
Stage IV: The melanoma has spread beyond the skin to other organs