The first sign of a melanoma is often the appearance of a new mole or a change in the appearance of an existing mole.
Normal moles are usually a single colour, round or oval in shape and not larger than 6mm (1/4 inch) in diameter.
Melanomas are more likely to have an irregular shape, be more than one colour, and are often larger than 6mm (1/4 inch) in diameter. A melanoma may also be itchy and may bleed.
A good way to tell the difference between a normal mole and a melanoma is to use the ABCDE checklist:
- A stands for asymmetrical – melanomas have two very different halves and are an irregular shape.
- B stands for border – unlike a normal mole, melanomas have a notched or ragged border.
- C stands for colours – melanomas will be a mix of two or more colours.
- D stands for diameter – unlike most moles, melanomas are larger than 6mm (1/4 inch) in diameter.
- E stands for enlargement or evolution – a mole that changes characteristics and size over time is more likely to be a melanoma.
Melanomas can appear anywhere on your body, but the back, legs, arms and face are the most common locations. Sometimes, they may develop underneath a nail.