There are three different types of skin cancer, and while melanoma is the least common, it’s both the most aggressive and the most serious.

Non-melanoma skin cancer refers to a group of cancers that slowly develop in the upper layers of your skin. The two most common types of non-melanoma skin cancer are basal cell carcinoma and squamous cell carcinoma

What is melanoma?

Melanoma is a cancer of the pigment cells (melanocytes) in the skin, which if not treated can spread very quickly through the body.

• Melanocytes not only contribute to skin pigmentation, they are also the cells that respond to ultraviolet light, and induce the tanning response. They are our frontline.
• Moles and freckles are collections of melanocytes many of us have, but in some cases, these collections of melanocytes can become cancerous and start to grow.
• If they start to grow downwards into the skin’s dermis layer, the cancer will come into contact with lymph vessels and can spread through these vessels to distant sites (this spreading is called metastasis). It very important to remove a melanoma while it is still thin, before it penetrates to these deeper layers of the skin.
• Rates of melanoma are over five times higher in New Zealand Europeans compared with Māori and Pacific peoples.
• Here’s more to know about melanoma

The most common areas for melanoma are those exposed to the sun, but melanoma can develop in any skin type cells in the body, even areas not exposed to the sun

Find out more about basal cell carcinoma

Find out more about squamous cell carcinoma

How is melanoma identified?

Melanomas usually appear as a changed mole or freckle, so if any mole or freckle changes, get it checked out.

One simple way to remember the signs and symptoms of melanoma is the mnemonic ABCDE:

• Asymmetrical – the mole, freckle or lesion is not round.
• Border – the border is irregular or not well defined.
• Colour – melanomas usually have multiple colours or are dark (or have no colour at all).
• Diameter – moles greater than 5 mm are more likely to be melanomas than smaller moles.
• Evolution – any change should be looked at.

Moles that develop later in life should also be looked at quickly.

Treatment of melanoma

It is vital to catch melanoma early when the chances of getting on top of it are highest. Early detection is the key.

Like the other types of skin cancer, the most effective treatment is surgical removal.  The thinner the melanoma, the less it has burrowed into the skin and the better the outcome. Once the melanoma has spread (metastasised), there are way fewer treatment options available

Chemotherapy and immunotherapy can be used and occasionally show very good success, but generally, the success once a melanoma has metastasised is very low. The five-year survival rate is unfortunately less than 10%.

Check your skin regularly, and if you note anything unusual, you must do something about it. Visit your doctor and start the process.