Medically reviewed by Dr. A.M. van Coevorden, dermatologist
Molesharmless brown spots of pigment, some worth keeping an eye on
Moles are harmless clusters of pigment cells in the skin. Almost everyone has them, on average about 25. They are normal and usually harmless. Even so, it is important to keep an eye on a changing mole, because in rare cases a mole can turn malignant (a melanoma).
What are moles?
Moles are benign clusters of pigment cells in the skin. That is normal; almost everyone gets moles, on average about 25. Besides normal, benign moles there are malignant moles, melanomas.
How do you get moles?
Most moles develop between the ages of three and twenty. Sometimes a mole is present at birth (a congenital mole). The number is partly determined by heredity, and sunlight also affects how many you have.
What do moles look like?
Ordinary moles are usually brown and can be flat, raised or bumpy. They vary in size, shape and colour, but characteristically the shape and colour are regular. A separate form is the atypical mole: more irregular in shape and colour, often with different shades of brown side by side and sometimes a reddish edge. These are benign, but someone with many of them has a slightly higher chance of a melanoma.
Why is it important to check moles?
It is important to keep a close eye on a changing mole, because it could turn malignant. See your GP or dermatologist if a mole: grows larger; changes colour (a malignant mole often has several shades of brown and sometimes black, red, purple, blue, grey or white); changes shape (becomes asymmetric or irregular); itches, stings or hurts; forms crusts; bleeds; or stands out because it looks different from the others. Go to the doctor for sure if there are two or more of these changes. The doctor can check whether there is a malignant change.
Risk factors for melanoma
Important risk factors are: heredity, if several family members have had a melanoma; many ordinary moles (more than 100) or five or more atypical moles; fair skin with freckles or blond or reddish hair; sunburn at a young age; use of a sunbed; and a congenital mole larger than 20 cm.
Are moles contagious?
No. Moles are clusters of your own pigment cells in the skin and cannot be passed from person to person.
How is the diagnosis made?
The GP or dermatologist can often tell from the spot whether it is a benign mole or a melanoma, sometimes with a dermatoscope that magnifies the mole many times. In case of doubt or clear suspicion of melanoma, microscopic examination is needed, for which the mole is removed under local anaesthetic.
What treatments are there?
A normal mole does not need treatment. Sometimes an irritating mole is removed, for example under a waistband or bra strap, or for cosmetic reasons. This can be done by cutting out (excision), shaving off (shave) or burning off (electrocoagulation). If there is even a small suspicion of a melanoma, the mole is cut out and examined under the microscope.
What can you do yourself?
Avoid sunburn and protect children well. Do not use a sunbed. Know your own skin and check your moles, if helpful with photos and someone looking with you. See your GP or dermatologist if you get a new, odd mole or when moles change or cause symptoms.
Frequently asked questions about moles
Are moles dangerous?
Usually not; most are benign. In rare cases a mole can turn malignant, which is why it matters to keep an eye on changes.
When should I see a doctor?
If a mole grows, changes colour or shape, itches, bleeds, crusts or stands out from the rest. Certainly with two or more of these changes.
What is an atypical mole?
A mole that is more irregular in shape and colour. It is benign, but having many raises the chance of a melanoma slightly.
Should moles be removed?
A normal mole should not. Removal is done for irritation, for cosmetic reasons, or always when a melanoma is suspected, followed by microscopic examination.
How do I protect myself?
Avoid sunburn, do not use a sunbed, and check your own skin regularly, if helpful comparing with photos.