Moles can be round, oval, flat, or raised. They can occur singly or in clusters on any part of the body. Most moles are brown, but colors can range from pinkish flesh tones to yellow, dark blue, or black. They may be present at birth, but most appear later.
Certain types of moles are more likely to develop into skin cancer:
- If you have a large congenital melanocytic naevus, there is a one in 20 risk that it may become cancerous. Smaller congenital naevi are less likely to develop cancerous change.
- Dysplastic naevi are more likely to progress into a malignant melanoma (a type of cancer).
An easy way to remember these changes and what to do if you notice any of them is to use the ABCDE method.
A – Asymmetry
B – Border
C – Colour
D – Diameter
E – E stands for EVOLVING; a mole or skin lesion that looks different from the rest or is changing in size, shape, or color, or starts to itch, bleed or ulcerate without any trauma.
What cause Moles?
The exact reasons why moles develop are not fully understood at present. However, many types seem to run in families, particularly dysplastic naevi. The likelihood of having lots of moles also seems to be inherited. You are more likely to have moles if you spend lots of time in the sun, especially if you have done so since childhood.
Moles can also appear because of changes in your hormones. This commonly occurs:
- during adolescence
- if you are taking the contraceptive pill
- during pregnancy
- during the menopause
It’s a good idea to check your moles regularly so that you are aware if any of them change shape or colour. You should see a dermatologist if you notice:
- growth of an existing mole
- a mole with a ragged/uneven edge
- a mole of varying shades of colour
- a mole that bleeds, oozes or crusts
- a mole that feels painful or itches
- a mole where the two halves don’t look the same