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ABCDEs of melanoma skin cancer

Photos of various melanoma, showing one with asymmetry, one with border irregularity, one with varied color, and one larger than ¼ inch, and three images showing evolution of size of melanoma.

Source: NCI Visuals Online. Skin Cancer Foundation. www.cancer.gov.

The ABCDEs of melanoma skin cancer are:

  • Asymmetry. One half doesn't match the appearance of the other half.
  • Border irregularity. The edges are ragged, notched, or blurred.
  • Color. The color (pigmentation) is not uniform. Shades of tan, brown, and black are present. Dashes of red, white, and blue add to a mottled appearance.
  • Diameter. The size of the mole is greater than 1/4 inch (6 mm), about the size of a pencil eraser. Any growth of a mole should be evaluated.
  • Evolution. There is a change in the size, shape, symptoms (such as itching or tenderness), surface (especially bleeding), or color of a mole.

Current as of: October 25, 2023

Author: Healthwise Staff
Clinical Review Board
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