Melanoma – the most aggressive form of skin cancer – often develops as a new lesion but can sometimes develop from a pre-existing mole. It is usually curable if it’s caught very early. That’s why it’s important to know the difference between normal moles and moles that might be dangerous.
This month, Women’s Health Matters spoke with Dr. Jensen Yeung, medical director of the Ricky Kanee Schachter Dermatology Centre and the Phototherapy Education and Research Centre at Women’s College Hospital, about how to monitor your own skin for suspicious moles.
“About 70 to 75 per cent of melanomas are detected by patients themselves,” says Dr. Yeung. He recommends that patients do a self-check of their skin once a month.
“The common sites of melanoma are on the back, on the back of the legs, on the face, and, in dark-skinned individuals, on the palms and soles, and on the nails,” says Dr. Yeung. “But melanoma can occur anywhere on the body.”
That means you should check all skin areas, including hands, feet, scalp, and especially the back. If you don’t have anyone to look at your back for you, use two mirrors to get a good view of your own back.
When you’re examining moles, follow the ABCDE rules and look for any of the following suspicious signs:
A for asymmetry: if you draw a line down the centre of a mole, and the two halves do not match.
B for borders: the borders of the mole are irregular or uneven instead of smooth.
C for colour: the mole is more than one colour or has uneven colouring.
D for diameter: if it’s more than six millimetres in diameter.
E for evolution: any change in size, shape or colour. This one – a changing mole – is the most important of the ABCDE characteristics.
Having any one of the danger signs doesn’t necessarily mean a mole is skin cancer, but do have a suspicious mole checked by a doctor.
In addition to the ABCDEs, Dr. Yeung also looks for what he calls “ugly duckling signs” – things that look out of the ordinary or out of place, that look different from the rest of the patient’s moles.
For people with lots of moles – more than 50 – it can be hard to keep track of whether a mole has changed or not. Dr. Yeung recommends having a set of photographs taken of their skin.
“Then they have something to compare it to, to see whether there are any new or changing nevi.”
In addition to monthly skin checks, sun safety is important in preventing melanoma. Dr. Yeung recommends trying to stay out of the sun when the UV index is highest (between 10 a.m. and 4 p.m.), and using sunscreen regularly. Use a sunscreen with an SPF of 30 or higher, apply it 15 minutes before sun exposure and reapply every two hours when outdoors.Jump to top page