What is Melanoma?

​​UV radiation from the sun causes two main types of skin cancers: melanoma, and non-melanoma skin cancers (squamous cell carcinomas and basal cell carcinomas). Melanoma develops in melanocytes – the type of cells that give colour to our skin, hair, and eyes. It is the most aggressive and life-threatening type of skin cancer due to its tendency to mutate and spread to other areas of the body. The cure rates differ greatly on the stage at the time of detection, which means regular skin assessments are very important for your health.

How common is melanoma in NZ?

Our clear air might make for beautiful views, but alongside the low levels of ozone protection, the lack of haze and humidity in our atmosphere actually exposes New Zealanders to high levels of UV rays all year round. What does that mean for our skin health? Unfortunately, this dangerous level of UV radiation means NZ has one of the world’s highest rates of skin cancers.

According to Melanoma New Zealand, approximately 4,000 Kiwis are diagnosed with melanoma every year, making it the third most common cancer in NZ. Melanoma claims the lives of over 350 New Zealanders each year, and accounts for around 80% of skin cancer-related deaths in the country.

These sobering statistics might sound scary, but there are plenty of ways you can protect yourself and your loved ones. This article will outline the most effective preventative habits to help lower your risk of melanoma.


What does melanoma look like?

There is no single, fail-safe way to tell the difference between melanoma and a normal mole. However there are tools which can help you, such as the ABCDE acronym, which outlines several common melanoma warning signs seen in moles and lesions.

The ABCDE system urges us to look for:

  • Asymmetry: When one half is a different shape to the other.
  • Border irregularity: unclear, jagged or uneven edges.
  • Colour change: Multiple, uneven, changing colours and/or an irregular colour.
  • Diameter: Moles or lesions with a diameter of over 6 millimetres.
  • Evolving features: Changes in pain, texture, size, or starting to bleed.

Another way is to follow the so-called ‘Ugly Duckling’ rule. It might sound like the stuff of fairytales, but the Ugly Duckling rule refers to a method of comparing your moles. By checking yourself thoroughly and noting any moles or lesions that stand out as an Ugly Duckling, you can spot a potentially dangerous mole and head to a spot check for peace of mind.

Prevention and Early Detection

Protecting yourself and your family from melanoma – and all skin cancers – is a two pronged attack. First, do whatever is in your power to limit your risk by practising sun safety and reducing your exposure to dangerous UV radiation. Second, raise your chances of early detection by committing to both a thorough self-checking routine and regular assessments by dedicated skin specialists.

Sun Safety Tips to Protect Your Skin

According to the Cancer Society of New Zealand, over 90% of skin cancer is caused by excessive sun exposure. They recommend that we avoid spending too much time in the sun between 10am and 4pm during September to April, or whenever the ultraviolet index (UVI) rises over three.

But how do we actually avoid UV radiation, or limit the damage? The Cancer Society of New Zealand’s SunSmart campaign makes sun safety easy with the catchphrase ‘Slip, Slop, Slap, and Wrap!’

SLIP on clothes that cover up as much skin as possible. Dark colours give you the best protection. And don’t forget to slip into a shady spot when the sun is at its hottest!

SLOP on a broad-spectrum sunscreen every day, at least 20 minutes before you leave the house. Make sure you use enough to adequately cover each part of your body. Reapply every two hours, or sooner if you’ve had a dip in the water or been sweating heavily. (Do we do internal links? Could add ‘Read our article on the best sunscreens for skin cancer prevention to learn more about safe sunscreen use.’)

SLAP on a hat – extra points for a nice, wide-brim or flaps that cover your neck and ears. After all, the face and neck is the most common area to get sunburnt.

WRAP on a pair of close-fitting sunglasses with proven UV protection – don’t just pick a pair that makes you look good!


Early Detection Saves Lives

The earlier melanoma is detected, the better your outcome. Commit to a thorough self-checking routine and regular skin checks by a dedicated specialist, and keep an eye out for any moles, spots, or lesions that are new or changing. We recommend that every 3 months you set aside some time to have a proper look, or even better, get someone else to help so you don’t miss those hard to see areas. Refer back to the ABCDE system and Ugly Duckling rule for guidance, and if you notice anything out of the ordinary, book a spot check!

Regular mole checks from a skin health specialist will track and detect any suspicious changes and provide you with excellent protection from skin cancers. Mole skin checks differ depending on the clinic, but at NZ Skin Health you will receive a head-to-toe visual assessment, alongside the use of specialised technology to image and document your skin – making note of any potentially dangerous lesions or moles. Mole checks are done by saving images onto a digital diagram which enables specialists to monitor and track your skin health.

Diagnosis and Stages

In the early stages of melanoma, a visual diagnosis can often be made and treatment taken by simply excising the suspicious mole or lesion – aka it will be cut out of the skin.

In other situations, a biopsy might be taken and sent to a lab for a pathologist to examine and give a diagnosis. Blood tests, X-rays, and CT, PET, and MRI scans can also be used to gain a better understanding of how far, if at all, the cancer has metastasized (spread).

Once a diagnosis is made, melanoma is staged. This depends on a few factors, including thickness, and how far the cancer has spread. Here in New Zealand, most skin specialists use a framework from the American Joint Committee of Cancer (AJCC) when diagnosing the stage of a melanoma.

The stages are:

Stage 0 – In situ. It only occurs in the skin’s top layer.

Stage 1 – Thin. It is 2mm or smaller in thickness, or less than or equal to 1mm if there is ulceration.

Stage 2 – Thick. It is greater than 2mm in thickness, or 1mm if there is ulceration.

Stage 3 – It has spread to local lymph nodes.

Stage 4 – It has spread and secondary cancers are found elsewhere in the body.



Melanoma is treated with surgery, immunotherapy, and radiotherapy. The type of treatment depends on the stage, and might consist of one or all different forms of treatment in combination.

Early-stage melanoma can be as simple as removing the mole. However, if cancer has spread to other parts of the body, additional treatments such as immunotherapy and radiotherapy are used.


Worried? NZ Skin Health Can Help

NZ Skin Health is here to help you achieve peace of mind about your skin. Although people of all skin types benefit from regular skin checks, they are crucial for people with fair skin, or a family history of melanoma, who are at higher risk. We understand that cost can be a concern, so our gentle, highly-trained skin specialists will perform your first spot check free to put your mind at ease about our services.

Want to learn more about the skin screening process, or book an appointment with NZ Skin Health?

Call us on 09 533 41 41 or send us a message to book a skin assessment today.