Dermatologists remember the warning signs of melanoma with five letters. Run through them whenever you look at a mole:
A — Asymmetry. One half doesn't match the other.
B — Border. Edges are irregular, ragged, notched or blurred.
C — Colour. More than one shade — brown, black, red, white or blue.
D — Diameter. Larger than 6 mm (about a pencil eraser), though melanomas can be smaller.
E — Evolving. Changing in size, shape or colour, or a new symptom like itching or bleeding.
The most important letter is E: any spot that is changing deserves a doctor's look, even if it doesn't tick the other boxes. Watch also for the "ugly duckling" — a mole that looks different from all your others.
This rule is a guide, not a diagnosis. When in doubt, get it checked.
Educational only. This is not medical advice and cannot rule out skin cancer. See a dermatologist for anything new, changing or concerning.
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