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ABCDEs of melanoma skin cancer

Photos of various melanoma, showing one with asymmetry, one with border irregularity, one with varied colour, and one larger than 1/2 centimetre, 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.
Colour. The colour (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 6 mm (1/4 inch), 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 colour of a mole.

Current as of: October 25, 2023

Author: Healthwise Staff
Clinical Review Board
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ABCDEs of melanoma skin cancer