Skin cancer

Skin cancer is the uncontrolled growth of abnormal skin cells. It is the most common cancer affecting New Zealanders; however, it is largely preventable. If you protect your skin from the sun throughout your life, you will greatly reduce your risk of skin cancer.

Key points

  1. Skin cancers are classified into two groups – melanoma and non-melanoma (which includes basal cell carcinoma and squamous cell carcinoma). See types of skin cancer
  2. Melanoma is the most serious skin cancer and is the cause of more than 2 in 3 skin cancer deaths.
  3. Over 90% of all skin cancer is due to excess sun exposure.
  4. Protect your skin from the sun by being SunSmart and remembering to 'slip, slop, slap and wrap'.
  5. Do regular skin checks so that you get to know your skin and notice any changes.
  6. When found early, most skin cancers can be successfully treated. See a doctor if you notice dark, pigmented moles or skin spots, or ones that are crusted or bleeding.

What causes skin cancer?

Most skin cancer is caused by ultraviolet (UV) light damaging your skin’s cells. The main source of UV light is the sun. Artificial sources of UV light, such as sunlamps or tanning beds, can also increase your risk of skin cancer. 

Protecting your skin from the sun (and not using sunbeds) combined with regular skin checks, is the best way to prevent skin cancer.

Who is at risk of skin cancer?

People of all ages and skin colours can be diagnosed with skin cancer but those at a higher risk are people who have:

  • fair, light-coloured skin
  • skin that burns easily
  • had one or more severe sunburn, especially as a child
  • spent a lot of time outdoors unprotected from the sun
  • used sunbeds, particularly at a young age
  • a family history of skin cancer
  • a large number of moles or large, irregularly shaped and unevenly coloured moles.

New Zealand’s skin cancer rates are among the highest in the world

Our high skin cancer rates are due to:

  • high levels of UV radiation during daylight-saving months
  • low ozone levels
  • our outdoor lifestyle
  • a high proportion of people with fair skin.

What are the signs of skin cancer?

Most of us have freckles, moles or other spots on our skin. This is normal. However, you should see your doctor or skin specialist if you have a freckle, mole or spot that:

  • is new or changing
  • does not heal
  • looks different from others around it
  • has changed in size, thickness, shape, colour
  • has started to bleed.

When should I get my skin checked?

Have your skin checked by a doctor immediately if you notice any of the changes described above.

Your GP can also perform a skin check in combination with a general health check-up. If you are at higher risk of skin cancer, you may need regular skin checks as advised by your doctor. 

All New Zealanders should become familiar with their skin by doing regular skin self-checks (preferably once every 3 months). Being familiar with your skin means you will be more likely to notice any suspicious lumps or spots as soon as they develop, and at a stage when they can be successfully treated. 

Skin checks are particularly important if you are over 50, have a family history of skin cancer or have had any bad sunburn as a child. 

Learn how to do a skin check

How is skin cancer treated?

Unlike many other forms of cancer, skin cancer is often visible, making it easier to detect in the early stages. Early detection is the key to successful treatment.

Treatment depends on the type, size, location and number of skin cancers, and whether the cancer has spread to other parts of your body.

Many skin cancers are treated at your doctor’s surgery and do not need specialist treatment. Others forms of skin cancer may require more specialised surgery.  

Skin cancers that are detected early are likely to result in less extensive surgery.

See skin cancer treatment

How can I reduce my risk of skin cancer?

Skin cancer is largely preventable. Over 90% of all skin cancer cases are caused by excess sun exposure. If you protect your skin and avoid sunburn throughout your life, you will greatly reduce your risk of skin cancer.

Be SunSmart in the months between September and April, especially between the hours of 10am–4pm when UV radiation levels are very high. Don't just use protection on hot and sunny days; UV can still be damaging on cool, cloudy days.

In winter it is also important to be SunSmart at high altitudes and around snow or water.

Steps to being SunSmart: 

  • Slip into shade where possible.
  • Slip  on some sun protective clothing, for example, a shirt with a collar and long sleeves, and trousers or long-legged shorts.
  • Slop  on broad-spectrum sunscreen that has a sun protection factor (SPF) of at least 30. Apply 20 minutes before you go outside, and re-apply every two hours, especially if you are swimming or sweating. 
  • Slap  on a hat that protects your face, head, neck and ears.
  • Wrap  on some close-fitting sunglasses.

What if I have had a lot of sun exposure in my life?

Before the dangers of sun exposure were fully understood, many New Zealanders spent a lot of time outdoors without sun protection or used tanning beds. If you are worried you may have increased your risk of skin cancer in this way, the key is to prevent further skin damage and to have regular skin checks with your doctor. If you notice any darker, growing or changing moles, get them checked straight away.

Ways to protect your skin

  • Avoid outdoor activities when the sun is strongest – between 10 am and 4 pm during September to April in New Zealand
  • Wear sunscreen and lip balm daily that offer SPF 30 or higher sun protection.
  • Use sunscreen that offers broad-spectrum (UVA/UVB) protection and is water resistant. 
  • Apply the sunscreen and lip balm to dry skin 15 minutes before going outdoors. 
  • Apply the sunscreen to every part of your body that will not be covered by clothing. Reapply it every two hours if you are swimming or sweating.
  • Whenever possible, wear a wide-brimmed hat, long sleeves and long pants. 
  • Wear sunglasses to protect the skin around your eyes. 
  • Avoid getting a tan and never use a tanning bed or sun lamp. 

See sun safety

Support

The Cancer Society povide a wide range of support and resources to help people and their families living with any form of cancer.

Emotions & cancer Cancer Society of NZ, 2010
How we can help Cancer Society of NZ
NZ cancer services - find a hospital/service near you Healthpoint
More skin cancer support groups

Learn more

The Cancer Society and SunSmart website have a range of useful information sheets:

Skin cancer

Sun protection

Sunbeds

Vitamin D

General topics

Credits: Health Navigator Editorial Team.