Moles (Naevus)
What are moles?
  • The proper term for moles that are melanocytic, meaning consisting of melanocytes, is naevus.
  • Moles are collections of pigment producing cells (known as melanocytes) that reside towards the top layer of the skin.
  • Moles generally can be flesh-coloured, brown, blue or black. The majority of moles on skin are flat but raised moles are commonly seen.
Why do moles occur?
  • Moles are a natural part of skin development and are influenced by genetics and sun exposure.
When do moles develop?
  • Some moles are present at birth.
  • The majority of moles, however, develop during our childhood and young adulthood.
  • We continue to develop new moles on our skin in our 30’s and 40’s.
Do moles change normally?
  • Moles are made up of living cells called melanocytes.
  • They may respond to sunlight and UV exposure by producing more melanin, making them darker with sun exposure.
  • They can also respond to hormonal changes in puberty, pregnancy and sometimes hormonal therapy.
  • These changes are generally very small, uniform and apply to all nearby moles at the same time.
What do moles look like?
  • Moles can develop anywhere on the skin.
  • Their locations can influence their appearance.
  • This is important when trying to differentiate a normal mole from a cancerous mole.

Moles can have a variety of appearance 
When is a mole cancerous?
  • A cancerous mole is also known as a melanoma, one of the most aggressive forms of skin cancers.
  • A cancerous mole (melanoma) can arise from a previously “normal” mole or as a new growth on the skin.
What do I look for in a suspicious mole?
  • An abnormal mole may be a melanoma.
  • Melanoma arises from growths of abnormal melanocytes. They can change by multiplying their number of cells, and growing in abnormal arrangements.
  • They may also change by producing more pigment therefore becoming darker.
  • Some melanoma do not produce pigment and do not have dark pigmentation.
I have a lot of moles. Should I be concerned?
  • The more moles you have, the higher the risk of melanoma.
  • It means that your melanocytes have the right genetics to grow.
  • It may also be due to exposure to excessive sunlight during the early childhood years.
  • You should therefore avoid excessive sun exposure and in particular sunburn.
  • It may be much harder for you to monitor the moles by yourself. You should consider having regular mole checks.
I have noticed a change in a mole
  • This is the time to seek an expert opinion on the mole, such as from a skin cancer doctor or a dermatologist.
  • The mole should be examined with a technique called dermoscopy in a comprehensive skin cancer check.