What are moles?

Moles are normal overgrowths the skin cells that produce pigment, called melanocytes. They can be flat or raised. Their colour can range from skin coloured to pink to brown or black.

You are not usually born with moles, but by age 15 you may have around 50 moles. Moles can appear anywhere on your body, including palms and soles, nails, genitals, scalp and eyes.

Moles are different to freckles. Freckles are flat and only appear on the face of fair-skinned children or the shoulders after sunburn. They are due to the pigment in the pigment cells becoming darker with sun exposure.

Your doctor may use the word ‘naevus’, which is another word for mole.

What are the different types of moles?

You may see different words that describe moles:

• Benign naevus/mole is a normal mole. It is harmless.
• Congenital naevus/mole is a mole that you are born with, or that develops shortly after birth.
• Blue naevus/mole is a mole that looks blue. The blue colour is caused by the pigment being deep in the skin. They are usually harmless.
• Dysplastic mole or an atypical naevus/mole, is usually larger than other moles (larger than 5 mm). It often has an undefined border, uneven colour, irregular shape and some pinkness. Some of the features of dysplastic moles are similar to features of melanomas. Even though they are a risk factor for melanoma, they rarely become melanoma. They do not normally need to be removed.

Can my mole become a skin cancer?

Most moles are harmless, but there is a very small chance (around 1 in 10,000) a mole will change and become a melanoma. If you have a large number of moles (more than 100) or if you had a lot of sun exposure in childhood, you are at increased risk of developing melanoma.

Dysplastic moles are an additional risk factor for melanoma. The risk of melanoma increases as the number of moles and dysplastic moles you have increases.

How are moles diagnosed?

Regular skin checks performed by your doctor are important, especially if you have a large number of moles or several dysplastic moles. All of your skin needs to be checked, not just your moles, as melanomas can start as new spots.

Your doctor will most likely use a dermatoscope (a hand-held tool with a light and a magnifier) to check if a mole has features that are suspicious for cancer. They may also use photographs to compare your moles over time, from one skin check to the next.

You should self-examine your skin at least every 3 to 4 months and tell your doctor if you notice any moles that are new, growing or changing.

Check your moles regularly and look out for the following:

• increasing size
• changing shape
• changes to the colour — look out for moles that have several colours or shades
• any bleeding or itching
• new moles which look different or unusual

If you have a mole, avoid scratching or picking it — keeping children’s fingernails short and trimmed may help stop them scratching their moles.

If your mole is in a vulnerable area where it could be knocked or scraped against something, you should try to protect it.

How are moles removed?

Most skin spots that look like moles do no need to be removed. Your doctor may recommend you have a mole removed if it is larger than usual or if it looks like it may be cancerous.

If you need to have a mole removed, the doctor will give you a local anaesthetic to numb the area. they will then cut or shave the mole off with a surgical blade or use a hollow tube with a sharp end (punch device) to remove the mole.

You may have stitches to the area and a dressing to cover the wound and keep it clean until your skin heals.

After a mole is removed, you should take care to keep the wound area clean and use pain relief medicine if needed. Tell your doctor if the wound develops redness, swelling, worsening pain or discharge.

Can moles be prevented?

The number of moles you have is largely due to the genes you inherit. Exposure to sunlight, especially in childhood and early teenage years also affects if new moles develop.

You should avoid too much sun exposure and protect your skin by wearing tightly woven long sleeved clothing, broad brimmed hats and sunglasses and applying sunscreen regularly.

Resources and support

Read more on moles on the Australian College of Dermatologists website.

The Cancer Council has information on skin protection and screening programs.

Look at healthdirect's guide for sun protection, to help avoid too much sun exposure.