How to check a mole

  • Overview
Cancer Skin
Dr Unnati Desai Dr Unnati Desai National Lead for GP Services
In a land as often dreary as the UK, is skin cancer really a problem? Nuffield Health GP and mole expert Unnati Desai discusses the facts around skin cancer and provides a simple guide to checking your moles.

Melanoma is the fifth most common cancer in the UK, with over 16,000 people being diagnosed with melanoma in the UK every year (Source: Cancer Research UK). So skin cancer isn't just a problem in the southern hemisphere, it’s on our doorsteps.

It can be difficult to tell the difference between a non-cancerous mole and a cancerous one, particularly if you have a lot of moles or freckles. But there are some tell-tale signs that you can look out for. This comprehensive mole checking method you can use at home provides a good basis for identification of potentially troublesome moles.

What to look for when checking a mole

1. Are your moles symmetrical?

Normal moles or freckles are completely symmetrical. If you were to draw a line through a normal spot, you would have two symmetrical halves. In cases of skin cancer, spots don't look the same on both sides.

2. How do the edges feel?

Pay attention to any spots, blemishes, or moles with jagged edges. This includes abnormalities with blurry corners or 'shadowing' underneath their border.

3. Do they change colour?

A mole that is more than one hue is suspicious and should be evaluated by a doctor. This can include lightening or darkening of the mole. Melanoma cells usually continue to produce melanin, which accounts for the cancers appearing in mixed shades of tan, brown and black.

4. Are they still growing?

Elevation means the mole is raised above the surface and has an uneven surface. Evolving means changing in size, shape, colour. Look out for either of these when mapping/assessing your moles at home.

5. How big are they?

Any mole that's larger than 6mm in diameter should be checked and assessed by a doctor.

When to get a mole checked

Moles can develop on any area of your skin, so you should check yourself thoroughly at least once a month using the A – G method provided above. If you notice something unusual or concerning, speak to your doctor immediately for advice. They may advise mole mapping or mole assessment.

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

Last updated Friday 3 May 2024

First published on Monday 23 May 2016

Cancer Skin