ABCDE of moles

Most moles are harmless, but in a few rare cases they can develop into an aggressive form of skin cancer called malignant melanoma. You can check your moles by learning the ABCDE of moles. This covers a range of features that can help you spot if a mole is becoming cancerous.

A: asymmetry

A normal, healthy mole is usually round due to the fact it grows evenly. This means it is symmetrical, with one side a mirror image of the other. The picture shows a melanoma that looks like it has grown at an uneven rate and is asymmetrical.

B: border

Melanomas often have ragged or blurred borders or edges. Normal, healthy moles tend to be much rounder with smooth, clearly-defined borders. The picture shows two examples of melanomas with ragged, blurred borders.

C: colour

A mole usually has one uniform colour whereas melanomas are often uneven in their colour. As the picture shows, a melanoma can have 2-3 shades of brown or black or varying shades of red and pink. A mole that is darkening is one possible sign that it is becoming cancerous.

D: diameter

Melanomas are usually larger than 6mm – or the width of a pencil. It is also common for the melanoma to continue to grow bigger. However, this is not a sure sign of malignant melanoma. A cancerous mole can be smaller than this and a perfectly healthy mole can be larger.

E: elevation or enlargement

A melanoma will often get bigger and may become raised above the skin’s surface. Inflammation or swelling is another sign that you need to see your GP for a check up. It is often the case that the original mole remains the same size, while an area around or under it appears to spread or swell. In addition, any new symptom such as bleeding, itching or crusting, may also be due to melanoma.