What is melanoma?

Melanoma, which means "black tumor," is the most dangerous type of skin cancer. It grows quickly and has the ability to spread to any organ. Early detection is important because treatment success is directly related to the size and depth of the cancerous growth.

Melanoma comes from skin cells called melanocytes. These cells produce melanin, the dark pigment that gives skin its color. Most melanomas are black or brown in color, but some are pink, red, purple, or skin-colored.

Any area of the body can be affected by melanoma. Men are more prone to develop melanoma on the trunk. Women are more likely to have melanoma on the arms and legs. About 30% of melanomas begin in existing moles, but the rest arise in normal skin.

How common is melanoma?

Melanoma accounts for only about 1% of all skin cancers, but causes the great majority of skin cancer-related deaths. It is one of the most common cancers in young people under 30, especially in young women.

The incidence of melanoma has been dramatically increasing over the past 30 years.

What are the signs of melanoma?

Knowing how to spot a melanoma is important because early melanomas are highly treatable. Melanoma can appear as moles, scaly patches, open sores, or raised bumps.

Use the American Academy of Dermatology's "ABCDE" memory device to learn the warning signs that a spot on your skin may be melanoma:

  • Asymmetry: One half does not match the other half.
  • Border: The edges are not smooth.
  • Color: The color is mottled and uneven, with shades of brown, black, gray, red, or white.
  • Diameter: The spot is greater than the tip of a pencil eraser (6.0 mm).
  • Evolving: The spot is new or changing in size, shape, or color.

Some melanomas do not fit the ABCDE rule, so tell your doctor about any sores that won't go away, unusual bumps or rashes, or changes in your skin or in any existing moles.

Another tool that can be used to recognize melanoma is the “ugly duckling” sign. If a mole looks different from the others, it is the ‘ugly duckling’ and should be seen by a dermatologist.

What causes melanoma?

Most experts agree that a major risk factor for melanoma is overexposure to sunlight, especially sunburns in youth. Ultraviolet (UV) radiation from tanning beds also increases the risk of melanoma and has been designated a carcinogen (cancer-causing) by the World Health Organization.

Although anyone can develop melanoma, an increased risk for developing the disease is seen in people with:

  • A personal history of melanoma.
  • A family history of melanoma.
  • Fair skin, freckles, blond or red hair, and blue eyes.
  • A history of prolonged or excessive sun exposure, including blistering sunburns.
  • A history of tanning bed use.
  • Many moles, especially “atypical” moles.
  • A weakened immune system.

Melanoma is more common in Caucasians but can occur in people of all skin types. Nonwhite individuals most often get melanoma on the palms, soles and nails.

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