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Melanoma is the most dangerous type of skin cancer. Although melanoma makes up only 4% of skin cancers, it causes 77% of skin cancer deaths. About 100,000 cases of melanoma are diagnosed each year.

Melanoma typically presents as a brown or black spot with irregularities in symmetry, border and color. Melanoma may develop within an existing mole or on previously normal appearing skin. Melanoma has a high fatality rate because its cells can break off and spread throughout the body (metastasize).

When melanoma is caught early, your chances for successful treatment are much higher.

The ABCDE Rule

(A) Asymmetry - One half doesn't match the other half.
(B) Border Irregularity - The edges are ragged, notched or blurred.
(C) Color - The pigmentation is not uniform. Shades of tan, brown, and black are present. Dashes of red, white, and blue add to the mottled appearance.
(D) Diameter - The width is greater than six millimeters (about the size of a pencil eraser). Any growth of a mole should be of concern.
  (E) Evolution: the symmetry, border, color, or diameter of a mole has changed over time.

The "ABCDE rule" is an easy guide to the usual signs of melanoma. Be on the look out and promptly notify your primary care physician or dermatologist about any spots that match the following description. Some melanomas do not fit the ABCDE rule described above, so it is important for you to notice changes in skin markings or new spots on your skin.

Other warning signs are:
  • A sore that does not heal
  • A new growth
  • Spread of pigment (color) from the border of a spot to surrounding skin
  • Redness or a new swelling beyond the border
  • Change in sensation – itchiness, tenderness, or pain
  • Change in the surface of a mole – scaling, oozing, bleeding, or the appearance of a bump or nodule
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(click on an image for a larger view)

Melanoma of the back
This 38 year old patient noticed that a previously flat mole had changed and become larger in diameter and protruded outward from his skin (This fulfills the E for Evolution rule of the ABCDE’s).

Melanoma of the nail bed
Melanoma can occur in unusual areas, including the hands, feet and even the eye

Melanoma of the posterior calf
This melanoma is asymmetric, has an irregular border, has multiple colors within the lesion (brown, black, tan) and is > 0.6cm in diameter.

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Updated: May 4, 2007
This information is for educational purposes only and is not intended to replace the advice of your doctor or health care provider. We encourage you to discuss with your doctor any questions or concerns you may have.
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