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(Malignant Melanoma)


The Manual's Editorial Staff

Reviewed/Revised Dec 2023
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What is melanoma?

Melanoma is a type of skin cancer. It starts in skin cells called melanocytes. Melanocytes make the brown substance that gives skin its color. So melanomas are usually a dark color. The cancer can start in normal skin or in a mole Moles Moles are small skin growths that can be anywhere on your body. They are usually dark in color and are round or oval. Almost everyone has some moles. Moles often first appear when you are a... read more Moles .

Melanoma isn't nearly as common as other skin cancers. However, it's more deadly.

Who is at risk for melanoma?

What are the symptoms of melanoma?

Melanomas can vary in the way they look. They can be:

  • Flat brown patches with a ragged border and small black spots

  • Raised brown patches with red, white, black, or blue spots

  • Firm red, black, or gray lumps

Melanoma is less common in dark-skinned people. If a dark-skinned person does get melanoma, it's often under the fingernails or toenails or on the palms or soles of the feet.

Symptoms of melanoma are any skin growth that is:

  • Getting bigger

  • Getting darker

  • Inflamed (red and swollen)

  • Spotty and changing color

  • Bleeding, or the skin over it breaks open

  • Itchy, tender, or painful

How can doctors tell if I have melanoma?

Doctors will do a biopsy (cut out a small sample of your tissue to look at under a microscope).

ABCDEs of melanoma

The warning signs of melanoma are sometimes called the ABCDEs of melanoma. The letters ABCDE stand for:

  • Asymmetry: the two halves of the skin growth aren't the same shape

  • Borders: the skin growth has a ragged border or blends into the surrounding skin

  • Color: the skin growth changes color, especially to brown, black, red, white, blue or a color different or darker than your other moles

  • Diameter: the skin growth is wider than a quarter inch (larger than the size of a pencil eraser)

  • Evolution: the skin growth appears when you're more than 30 years old, or has grown or changed recently

How do doctors treat melanoma?

If the melanoma spreads to other parts of your body, your doctor may try:

How can I prevent melanoma?

You can help prevent melanoma by limiting sun exposure:

  • Stay out of the sun—sit in the shade, try to avoid the sun between 10:00 am and 4:00 pm

  • Don't sunbathe or use tanning beds

  • Wear protective clothing, such as long-sleeved shirts, pants, and hats with broad brims

  • Use sunscreen that’s at least 30 sun protection factor (SPF)—it's important to use more sunscreen every 2 hours and after swimming or sweating

Visit your doctor at least once per year for a skin exam if you:

  • Have had melanoma before

  • Have many moles

See a doctor if you see a change in a skin growth that doesn't go away after a few weeks.

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