MyHealth.Alberta.ca Network

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: March 1, 2023

Author: Healthwise Staff
Medical Review:
Kathleen Romito MD - Family Medicine
Amy McMichael MD - Dermatology
Donald Sproule MDCM, CCFP - Family Medicine

This information does not replace the advice of a doctor. Healthwise, Incorporated, disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. Learn how we develop our content.

To learn more about Healthwise, visit Healthwise.org.

Include ImagesLarge Print

Important Phone Numbers

ABCDEs of melanoma skin cancer