The A - G guide to checking your moles

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.

Malignant melanoma is the ninth most common cancer in Europe, with more than 100,000 new cases diagnosed in 2012. UK malignant melanoma incidence rates are estimated to be the ninth highest in males in Europe, and seventh highest in females. So skin cancer is not just a problem in the southern hemisphere, it’s on our doorsteps.

The reasons for skin cancer in Europe could relate to a number of factors. Firstly, Europeans with fair or freckly skin, or who have burned in the past are at higher risk of developing a melanoma. This risk is made greater due to an assumption that our poor climate renders it unnecessary to use sun protection. Because UVA and UVB rays are able to cut through clouds we should always wear sun protection when we’re out and about, but many don’t.

Additionally, the use of sunbeds, particularly prevalent from the 1980s – 2000s, has been proven to cause skin cancer by exposing skin to high levels of UVA and UVB rays. A study published in December 2011 estimated that around 86% of malignant melanomas in the UK in 2010 were linked to exposure to UVR from the sun and sunbeds. So skin cancer presents a bigger risk in the UK than can be assumed and as with most cancers, early detection is crucial to preventing its spread.

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. The A – G method provides a good basis for identification of potentially troublesome moles. If you exhibit any of these indicators, visit your GP.

What to look for

A - Asymmetry

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.

B - Border

A mole or spot with blurry and/or jagged edges.

C - Colour

A mole that is more than one hue is suspicious and needs to be evaluated by a doctor. Normal spots are usually one colour. 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.

D - Diameter

If it is larger than a pencil eraser (about 1/4 inch or 6mm), it needs to be examined by a doctor. This includes areas that do not have any other abnormalities (colour, border, asymmetry). But, don't be fooled by size alone - it can be smaller.

E - Elevation/Evolving

Elevation means the mole is raised above the surface and has an uneven surface. Evolving means changing in size, shape, colour.

F – From firm to palpation

This means if any of your moles change from a firm consistency, to a softer, spongier consistency.

G – Growing progressively over 1 month

A mole should remain a consistent size. If your mole continues to grow over more than a month, speak to your doctor.

Last updated Monday 22 February 2021

First published on Monday 23 May 2016