Checking your moles: What you need to know

What are moles?

Moles are generally harmless growths that occur when skin cells that contain melanin, the pigment that colours your skin, clump up instead of spreading out evenly. This leads to a darkened area that might be flat or protrude from your skin. Most people have some moles, and their colour will depend on your natural skin tone.

What causes moles to appear?

Most of us will develop at least a few moles during the first 30 years of our lives, and this is especially likely if you are lighter-skinned. Moles can also occur due to natural hormonal changes within your body, particularly during your teenage years or if you are pregnant, and they may fade or disappear as you get older.

Existing moles can darken after exposure to UV rays from the sun or tanning beds, but this can also damage your skin cells and change the way they grow. This increases the risk of a mole developing into melanoma, a form of skin cancer that can spread to other parts of the body. Melanoma can affect people of any age, and it is the fifth most common cancer in the UK.

How to check on your moles

The majority of moles will not develop into melanoma, but it is important to keep an eye on them to pick up any signs that skin cancer may be developing before it becomes more serious. The British Association of Dermatologists recommend that you check the skin all over your body at least once a month. Moles can develop on areas that are not exposed to the sun so you should check every inch of your skin with the help of a mirror, relative or friend. It can be difficult to spot changes in a mole that you look at regularly, so you may find it useful to take photographs to compare the appearance of the mole over time.

The ABCDE method is a good way to monitor your moles and detect the possible warning signs of melanoma early on:

• Asymmetry – do the two halves of the mole look the same? The shape, colour or texture might be different
• Border – you should normally be able to clearly see where the mole ends and where normal skin begins. If the border is ragged, uneven or blurry this is abnormal
• Colour – you may notice that the mole is not a consistent colour throughout. It may have patches of different shades of pink, brown, black or purple
• Diameter – moles that are bigger than 6mm across are at a higher risk of being cancerous
• Evolving – any mole that grows or changes in appearance over weeks or months should be monitored closely. You should also watch for a mole becoming inflamed, or beginning to bleed, crust, or itch

Around 1 in 10 people will have a mole that has at least one of these abnormal characteristics, but only 1 in 10000 of these moles will turn out to be cancerous.

Should I worry about my moles?

If you notice any of the ABCDE characteristics listed above, or if you are at all concerned about a mole, you should speak to your doctor immediately. They will be able to examine your mole and help to determine if it needs investigating. If necessary, you may be referred to a skin specialist for a biopsy, where a small sample of the cells from the mole is taken to be looked at under a microscope. Smaller moles can sometimes be completely removed this way.

If the result of a biopsy shows that the mole in cancerous, then surgery will be recommended to have it fully removed. If melanoma is caught early, this treatment is often effective, but you will need to be even more vigilant in the future in case it reoccurs. Moles can also be removed for cosmetic reasons if you find them unsightly and they are bothering you.

Ways to reduce your melanoma risk

Skin damage, especially sunburn, from UV rays is the biggest avoidable risk factor for melanoma. With many people visiting hot and sunny locations during the summer, the risk of getting sunburnt is raised, but there are steps you can take to protect yourself. Unfortunately, many people continue to focus on getting tanned on holiday, and there is a false belief that a little sunburn is okay.

You should aim to avoid excessive sun exposure when you are outside. Here are some ways you can reduce your risk of getting skin damage from UV rays:

• Use sun cream before you go out in the sun and re-apply it regularly throughout the day. When you go swimming, you will need to put on fresh sun cream afterwards. If you are lighter-skinned, have lighter coloured eyes, naturally blonde or red hair, or if you already have a lot of freckles you will need to be particularly careful. You should aim to use sun cream that has a higher SPF rating of 30 or above
• Wear clothing that limits the areas of your skin directly exposed to the sun. Clothes made of lighter fabrics are useful for keeping you cool, and a cap or sun hat will protect your face. Sunglasses are also important for shielding your eyes
• Duck into the shade regularly to limit your time in direct sunlight. Avoid the sun when it is at its strongest during the middle part of the day
• Stay away from tanning beds as these also produce harmful UV rays that can damage your skin

Summary

Moles are a commonly-occurring form of skin growth and they are usually nothing to worry about. The majority of people will develop moles somewhere, and this is more likely if you have a lighter complexion. Remember that moles can develop on any area of your skin, so you should check yourself thoroughly at least once a month to monitor for any ABCDE characteristics. If you notice something unusual or concerning, speak to your doctor immediately for advice. You can reduce the chances of your moles developing into skin cancer by avoiding too much sun exposure, and in particular sunburn, by regularly applying sun cream and limiting the time you spend in the sun.