Melanoma is a type of skin cancer. Melanoma can spread throughout the body and is the most serious form of skin cancer. It can be cured more easily when it is detected and treated early.

Melanoma is a skin cancer

Melanoma is a skin cancer that begins in the cells that give your skin its colour. These cells (melanocytes) clump together to make the brown spots we call moles. Melanoma can develop in an existing mole or can start as a new spot.

Melanoma begins in a deeper layer of the skin than non-melanoma skin cancer. It can grow and spread more quickly than non-melanoma skin cancer. It can spread to other parts of your body through your bloodstream if it is not treated early.

Melanoma is the most serious type of skin cancer and the most life-threatening.

Causes of melanoma

The main cause of melanoma is lifetime exposure to ultraviolet (UV) light from the sun, including sunburns at any age. Aotearoa New Zealand has very high UV levels and a high rate of melanoma. Tanning sunbeds are another strong source of UV light.

Excessive UV light damages the cells (the building blocks) in your skin. They then grow in an abnormal or uncontrolled way and become cancerous.

Risks for melanoma

Most melanomas are in people older than 50. The risk increases as you age, but younger people also get melanoma. 

You have a higher personal risk of melanoma if you:

  • have a light skin colour
  • have blonde, light or red hair, and blue eyes
  • form freckles and sunburn easily
  • have lots of moles (50 or more)
  • have large, irregularly shaped or unevenly coloured moles
  • have had skin cancer before
  • have whānau who have had skin cancer
  • spend a lot of time outdoors
  • have lowered immunity from other health conditions or medicines.

Symptoms of melanoma

Melanomas are often first noticed as an unusual looking freckle or mole that might itch or bleed.

Signs a mole could be a melanoma include it:

  • is new
  • looks different to the others around it
  • is changing in size, thickness, shape or colour
  • has started to itch, bleed or cause pain
  • has an uneven (asymmetrical) shape or an irregular edge
  • has different colours within it (possibly black, blue, white or red)
  • is not healing.

If you are concerned about any spots on your skin, have them checked by your healthcare provider.

Melanoma New Zealand has an ABCDEFG early detection system for melanoma and a video guide to skin self-checks. Use them when you check your own skin.

Early detection – Melanoma New Zealand (external link)

You can find images of melanomas on DermNet. 

Melanoma — DermNet (external link)

Diagnosing melanoma

Your healthcare provider will examine your skin and any moles that are new or have changed.

Your healthcare provider may be able to reassure you there is no skin cancer or you could have something that needs a closer look. They may use a dermatoscope (a small skin microscope) to allow a better view.

If you have a suspicious mole that could be melanoma, your healthcare provider is likely to recommend surgery to remove all of it. This is called a diagnostic excision. 

You will be given a local anaesthetic to numb the skin. The mole is removed whole with a narrow margin of healthy skin. It is sent to a laboratory to confirm whether it contains cancer cells and what type. You will be given stitches (sutures) to help your skin heal.

You may be referred to a more specialised healthcare provider for this surgery.

  • The laboratory report should guide any more investigations or treatments you need, if they found melanoma.
  • If the melanoma was in its early stages and was removed successfully, it may be cured.

Treating melanoma

Melanoma on most parts of the body can be cured with local surgery (diagnostic excision) if they are found at an early stage (0, I or II). This is possible for 90% of early-stage melanomas.

Some large or spreading melanomas need a bigger area of surrounding skin to be removed. This is called a wide local excision. It is often done by a plastic surgeon.

If the remaining skin cannot be pulled together and stitched you may need a skin graft. This means taking skin from another part of your body to put over where the melanoma was removed from.

Advanced melanoma

When melanoma spreads beyond the skin to other parts of the body it become more difficult to treat. If your cancer is more advanced, you may be referred to an oncologist (a cancer specialist). They may recommend additional treatments.

For more advanced melanoma you may need a combination of treatments, including:

  • surgery
  • drugs that kill cancer cells (chemotherapy)
  • drugs to stimulate your immune system (immunotherapy)
  • radiation therapy (x-ray therapy).

Depending on the stage of melanoma, you may need surgery to remove all the lymph nodes in the surrounding area. Lymph nodes are important sites in the spread of cancer.

Preventing melanoma

You can reduce your risk of skin cancers whatever your age. Keep yourself and your tamariki (children) safe from the sun.

Be sun safe

  • Try to avoid the sun between 10am and 4pm, September to April.
  • Find shade outdoors, if possible.
  • Cover up by wearing long-sleeved tops and pants.
  • Wear a wide-brimmed hat and UV-protective sunglasses.
  • Use high-SPF sunblock on exposed skin.

Do skin checks

Check your own skin about every 3 months. This will help you spot any changes early. Regular skin self-checks are important for all adults, but particularly if you:

  • are aged over 50
  • have a family history of skin cancer
  • are at higher risk of getting skin cancer
  • have had skin cancer.

Melanoma can return, even after one has been cured. It is important you keep checking your own skin and to attend follow-up appointments with your healthcare provider.

Melanoma New Zealand has a useful guide on how to do a skin self-check.

Early detection — Melanoma New Zealand (external link)

Photographic checks

If you have a higher risk of melanoma, you may consider having a photographic skin check (mole map) with a healthcare provider.

Learn how to be SunSmart (Haumaru rā) – Cancer Society (external link)

Cancer support

Once someone has been diagnosed with cancer, we know there are some difficult days ahead. No matter where you are on the cancer pathway, there is always someone to connect with for support.

There are local services available to help make things easier for you and your whānau.

Cancer support (search) — Healthpoint (external link)

There are a number of benefits of belonging to a support group.

Health-based support groups

Melanoma New Zealand

This website includes facts about melanoma, how to prevent it, skin check providers, and more.

DermNet NZ

This website has photographs of melanomas.


Learn how to keep safe while still living life in the sun.

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