Why are they of concern?
Atypical moles tend to be benign, but many experts believe that they are a big risk factor for melanoma and can become cancerous further down the line. According to the American Association of Dermatology (AAD), having atypical moles increases the chances that melanoma will develop in moles (both new ones and those that already exist on the body) or on normal skin.The more atypical moles you have, the more likely it is that you'll develop melanoma at some point in your life. The Skin Cancer Foundation suggests that anyone with at least ten atypical moles is twelve times more likely to develop melanoma in comparison to the general population. The risks are even greater if you've got close relatives who have been diagnosed with melanoma.
Things to look for
There are certain characteristics that determine whether a mole is likely to fall into the atypical category. Here are some of the main characteristics of atypical moles to help you spot the signs.- Size: An atypical mole will often be larger than a 'normal' mole. Conal Perrett, a Consultant Dermatologist at the Cadogan Clinic in London, explains that "if a mole is greater than 7mm in diameter (which is roughly the size of the blunt end of a pencil) or is growing rapidly, get it checked out."
- Shape and symmetry: Atypical moles tend to be an irregular shape, and are asymmetrical (not the same on both halves). If you were to draw an invisible line through a 'normal' mole, both halves should be a mirror image of one another but this isn't the case with atypical moles and each half can look very different to the other.
- Color: Generally speaking, atypical moles can range from a tan shade of brown through to a much darker shade. They will often vary in color though and won't necessarily be the same shade all over. For example, one area of the mole may be a darker or lighter shade than other areas. In particular, Perrett points to "color variation within a mole (for example if three or more colors are visible within it)."
- Texture: Atypical moles can have a raised-up appearance, although some are completely flat. They may also have a 'rough' appearance rather than being smooth-looking. Perrett recommends that you look for "a change in texture such as inflammation, bleeding, or crusting, along with any mole that becomes slightly raised or that becomes a lump on your skin that you can feel."
- Borders: The borders of an atypical mole can look flat and it may seem as though the edges of the mole are fading into the surrounding skin, rather than there being an obvious border that adds definition.
