Melanoma is the least common of the skin cancers but is the most dangerous if it is not found early.
Melanoma is a tumour of the melanocytes. Melanocytes are cells that produce melanin, which is responsible for the colour of skin, and protects it from harmful ultraviolet rays that come from the sun or sun tanning beds. When the skin is trying to protect itself it increases the amount of melanin, resulting in a suntan or moles.
People with naturally darker skin (brown or black) have the same number of melanocytes as people with white skin but they naturally make more melanin, which means more natural protection from UV rays.
Although it is still not clearly understood why melanomas occur, we do know that there are several factors that will significantly increase your risk, such as family history of melanoma, fair-skin, pre-exciting skin damage, having multiple atypical or dysplastic naevi (abnormal moles), blistering or peeling sunburns (especially before the age of 20) and too much exposure to the sun, especially in childhood.
For further information, please refer to Cancer Council Victoria – About Melanoma