There are different forms of skin cancer – the most aggressive is malignant melanoma. 13,000 people will face a diagnosis of melanoma here in the UK this year and sadly many of them will not survive the disease. Over half of all melanomas develop out of the blue, which is why you should always report a new pigmented mark anywhere on your skin. The remainder develop in existing moles, and that is why we ask you to keep an eye on your moles and report any change in size, shape or colour. A mole that starts itching or bleeding could also be turning cancerous and must always be checked out.
Kings College in London have been doing a lot of work in this field. They have been following 3,000 twins over many years and have come up with a simple formula. They suggest that people should count the moles on their right arm. If someone has more than 11 moles on the right arm, they are likely to have more than 100 moles over the entire body and this is associated with a five times increased risk of developing skin cancer. Individuals who fall into this category should certainly never use a sunbed and should use high sun protection factor. It is also worth talking to your GP about the possibility of referral to a mole mapping clinic. These are usually run by dermatologists who will examine your moles with a special device called a deramtoscope. They can take pictures and will then be able to pick up any changes quickly and like all cancers, the earlier the diagnosis, the better the outlook.
And don’t forget – it’s not just about checking the moles on your arms. The commonest site for melanoma in men is on the trunk and in women it is on the legs.