Risk factors

People at higher risk of skin cancer are those who:

  • previously had a skin cancer and/or have a family history of skin cancer
  • have a large number of moles on their skin
  • have a skin type that is sensitive to ultraviolet (UV) radiation and burns easily 
  • have a history of severe/blistering sunburns
  • spend lots of time outdoors, unprotected, during their lifetime
  • actively tan or use solariums or sunlamps
  • work outdoors.

Family history

Sun exposure is the cause of most skin cancer. Less than 5% of all melanomas can be explained by an inherited gene.

Risk factors for family skin cancer include:

  • a personal history of melanoma at an early age; the average age to be diagnosed with melanoma is 33 years
  • a personal history of more than one melanoma
  • many moles on your skin; more than 10 on the arms and 200 on the body
  • many unusual moles
  • a blood relative diagnosed with melanoma at an early age
  • a blood relative diagnosed with more than one melanoma
  • a blood relative diagnosed with melanoma of the eye.

A large number of moles

The more moles you have on your skin, the higher the risk of the most dangerous type of skin cancer – melanoma. 

Moles are overgrowths of melanocytes (a type of skin cell). We are not normally born with moles, but most of us will develop some on our skin by 15 years of age.

The number of moles we develop is determined by genetic (inherited) factors and exposure to ultraviolet (UV) radiation.

Australians tend to have more moles than people living in other countries, possibly because of childhood sun exposure.

What do moles look like?

Moles can range in colour. They are generally medium to dark brown but can also be skin-coloured or black.

The majority of moles are flat, relatively even in colour and regular in shape. Some moles are raised and these are usually soft to touch and lighter in colour.

Dysplastic moles

These moles look different to ordinary moles and may evolve to melanomas. If you have multiple dysplastic moles you are at greater risk of melanoma. Your doctor may recommend regular checks with a dermatologist (skin specialist).

See your doctor if you think you have moles with the following ‘dysplastic’ features:

  • larger than most moles
  • smudgy and irregular edges
  • uneven in colour
  • may have some pinkness.      
Skin types
Skin types which are more sensitive to ultraviolet (UV) radiation burn more quickly and are at a greater risk of skin cancer.