Melanoma is the least common but most serious type of skin cancer. Fortunately, most melanomas are curable if detected early.

A melanoma usually looks like an unusual freckle, typically with an irregular shape and uneven colour. It may have a mixture of colours, including brown, black, blue, red, grey and white. In the early stages, a melanoma is usually flat, but may become raised as it grows.

Melanoma most often appears as a new spot on normal skin. It can also develop over a period of months in an existing freckle or mole.

Sun exposure is the major risk factor for melanoma, especially repeated sunburn in the first 10 years of life. Other risk factors include fair skin and red hair, many 'dysplastic' moles and a close family member with melanoma. The risk increases with age.

Check your skin regularly for any new or changing spots, especially those that are different to the others around them. People at high risk should have regular checks at the surgery. Melanoma can develop in skin anywhere on the body.

Early detection is vital. Untreated, a melanoma can grow into the deeper layers of the skin and spread to other parts of the body. Diagnosis is by surgical removal, usually with local anaesthetic.

The best way to prevent melanoma is to reduce exposure to the sun, especially during the middle of the day. Use protective clothing, shade and a broad-spectrum sunscreen with a sun protection factor (SPF) of at least 30+. Reapply it regularly while in the sun.

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