Alberta Cancer Foundation

Mole Watch

Researchers first developed the ABCD system back in 1985, later adding the “E” step. Put it all together and it’s an easy-to-remember guide for scrutinizing suspicious moles. Do a body scan monthly, checking all areas, even those not typically exposed to the sun, and ask your physician about any new or pre-existing moles with the following characteristics:

Asymmetry: The shape of one half does not match the other.

Border: The mole’s edges are irregular, notched, or blurred.

Colour: A normal mole is one colour throughout. Watch for different shades of one colour, or different colours, such as black, brown and tan mixed with areas of white, grey, red, pink, or blue.

Diameter: The mole is usually larger sized, more than 5 mm, or the size of a pencil eraser.

Evolution: The most important sign is any change in an existing mole or the development of a new mole (size, colour or elevation) or new symptoms like bleeding, crusting or itching.