What causes melanoma?
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Most melanomas are caused by excessive sun exposure, along with genetic factors.
Melanoma is a type of skin cancer that develops in skin cells called melanocytes, which give skin its colour. It usually occurs on parts of the body that have had too much sun exposure but can also develop on areas that are rarely exposed to the sun. Ultraviolet (UV) radiation from the sun can damage the DNA in skin cells causing them to grow and divide in an uncontrolled way. Skin damage can happen in as little as 10-15 minutes of sun exposure. In fact, there is no safe amount of sun exposure. UV exposure accumulates over time and the longer skin is exposed to UV rays, the greater your risk of getting skin cancer. Some people are more at risk of developing melanoma due to their genetics. Having lots of moles (naevi), pale or freckled skin, and fair or red hair can all increase the chances of getting melanoma.
Did you know even on cloudy days you can still get burnt? Over 90% of UV rays can pass through a light cloud cover and cause sunburn. If anything, the risk of sun damage is higher on a cloudy day, because people are less likely to cover up. Adopt sun protective behaviours by following the “5 sun-safe” practices:
Slip on protective clothing, slop on sunscreen, slap on a hat, seek shade, and slide on sunglasses.
Melanoma is easiest to treat when detected early.
Most people diagnosed with melanoma do well after treatment, especially if the cancer hasn’t spread. However, when melanomas are detected later, when it is at a more advanced stage, it can be more dangerous and life-threatening. Due to the ongoing research and development of new drugs and new treatments, people diagnosed with more advanced melanoma now have much better chances of recovery than in the past.
If not treated early, melanoma may spread to other parts of the body and become life-threatening.
Melanoma usually begins in the top layer of the skin (called the epidermis) and is known as 'in-situ melanoma'. In most cases, in-situ melanomas do not grow out of the epidermis or become life-threatening. However, if not treated, some of these melanomas can grow deeper into the middle layer of the skin (dermis) where they are called 'invasive melanoma'. From there, these cancerous cells can spread through the blood or lymph system to organs like the lungs, liver and brain. This highlights the importance of being familiar with your skin, and if anything changes, seek medical advice so it can be treated early.
Who is at risk?
Anyone can develop melanoma. The risk is higher for people who have:
Been exposed to the sun without protection for extended period of time or when the UV index is 3 or above.
A family history of melanoma (parent, sibling or child).
Pale or freckled skin, especially if it tends to burn easily and doesn’t tan.
Blue or green eyes and fair or red hair.
A previous diagnosis of melanoma or another type of skin cancer.
Lots of moles (naevi), especially if those moles have an irregular shape or uneven colour.
A weakened immune system from using immunosuppressive medicines for a long time.
A history of sunburns that caused blistering, especially in childhood.
Remember, young people can also get melanoma.
The older you are, the more likely you are to have a melanoma. However, melanoma is also one of the most common cancer types diagnosed in teenagers and young adults. Getting too much sun exposure when you are young can increase your chance of getting melanoma later in life.
It is never too late to start protecting your skin. Sun damage builds up over time, so it is important for everyone, no matter what their age, to be familiar with their skin, avoid too much sun exposure, and see a doctor if they notice any changes or new moles, freckles or lumps.
Terri Grosser's story
Terri died of melanoma in 2024 after living with cancer for eight years. Her story teaches us that resilience inspires change and that early detection matters.
When Terri Grosser first noticed a changing mole on her thigh, she booked a check-up with her GP. She was 35 at the time, juggling life as a young mum with three children, and living in Charters Towers in Central Queensland. Her initial diagnosis of stage 3 melanoma would turn her family’s world upside down.
Over the years that followed, Terri went through more than 10 surgeries. Her family felt incredibly supported by their network in Mt Isa, and her openness about her diagnosis brought the community together – they organised a nightly “meal train”, supported the family emotionally and financially, and offered hands-on help.
Her sister, Kara Thompson, remembers it all vividly.
“The amount of financial, emotional and physical support throughout Terri’s journey was amazing…every night at 6 o’clock someone would rock up with a beautiful meal,” Kara said.
The local cancer care unit with its dedicated nurses helped Terri continue treatment close to home, and telehealth brought some appointments within reach. But major appointments – including scans and oncology consults – still meant flying nearly 2,000km to Brisbane.
“The preparation involved with each trip was huge,” Kara said. “Flights, accommodation, food, taxis – it just adds up.”
“There was always the recovery after surgery and the feeling of “Did they get all the cancer?... and it was tricky because with kids at that age, they don’t understand. They want mummy to keep doing everything. We tried to keep everything normal for the kids.”
Terri sadly passed away in 2024 after living with cancer for eight years, but her legacy lives on – not only in her three children, but in the countless people who were moved by her story to make time to book in for a skin screening checkup.
“If anyone could get anything out of my story, it’s please get your skin checked,” Terri told the ABC in 2021. “You need to get it checked every year, and if anything on your skin changes.”
Now, her family continues the work Terri started – urging others to prioritise skin checks and protect themselves from the sun, and advocating for better access to care in regional areas.
“We spread the message far and wide about people getting their skin checked.”
Make a donation to make a difference for Queensland families like Kara’s.
Types of melanoma
1. Superficial spreading melanoma
This is the most common type particularly among younger people. It commonly presents as the spread of dark pigmentation extending from an existing mole.
2. Nodular melanoma: This type of melanoma tends to be more aggressive and is more common in older people. It usually appears as a solid, raised growth that can be red, brown, pink or black, and it may develop a scaly crust that bleeds easily.
3. Lentigo maligna melanoma
This type often appears in adults over 40 and develops slowly. It typically presents as an irregular brown spot on the head or neck.
4. Acral lentiginous melanoma
This melanoma type affects the palms, soles, or under the nails, and is more common in people with darker skin tones.
How to spot melanoma?
Often melanoma has no symptoms, however, the first sign is generally a change in an existing mole or the appearance of a new spot. If you notice any of the changes listed in the illustrations here, consult your doctor.
Melanoma thickness
Melanoma thickness tells us how deep the cancer has grown into the skin. The deeper it goes, the more likely it is to spread, and this can affect how well treatment works.
Melanoma in-situ
At this stage the melanoma is confined to the epidermis, the outermost layer of the skin. The abnormal cells have not spread into the deeper layer beneath it, known as the dermis. Because the melanoma has not penetrated deeper skin layers, melanoma in-situ is classified as non‑invasive, meaning it cannot spread to other areas of the body if treated.
Thin melanomas
Thin melanomas are less than 1mm in thickness and are considered invasive if they have penetrated the dermis, the skin layer beneath the epidermis. Thin melanomas are usually successfully treated with good survival outcomes.
Thick melanomas
Thin melanoma can progress to a thick, more advanced melanoma if left untreated. Thicker melanomas have grown to more than 1 mm below the skin surface. They have a higher chance of spreading to other parts of the body and are harder to treat.
You can read more about melanoma thickness here.
Melanoma in Australia
Facts & figures:
Each year, around 17,800 Australians are diagnosed with an invasive melanoma, which means it has spread into the deeper layer of the skin.
On average, around 1,400 Australians die from melanoma every year.
Melanoma is the second most common cancer type diagnosed in men and the third most common cancer type in women (excluding non-melanoma skin cancers).
Melanomas can develop anywhere on the skin, but are more likely to be diagnosed on the chest and back in men, and on the legs and arms in women.
Geographical patterns in Australia
Melanoma diagnosis and survival rates are not the same across Australia – they vary depending on where people live. Many areas in south-east Queensland and northern New South Wales have higher than average diagnosis rates of melanoma (shown by red and orange colours in the map on the right). In contrast, areas in northern, central, and western Australia usually have lower than average diagnosis rates (shown in blue).
Let's take a closer look at how melanoma diagnosis and survival rates vary across Australia.
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1. The areas that have higher diagnosis rates for thin melanomas are also likely to have higher rates for thicker melanomas.
Many areas in south-east Queensland, northern New South Wales, as well as some parts of coastal northern Queensland and south-west Western Australia have higher than average diagnosis rates of melanoma.
This map shows the areas with higher than average diagnosis rates of thin melanoma. As you scroll down, you will notice on the next slide that many of the same areas have higher than average diagnosis rates for thick melanoma as well.
Scroll down ↓
2. Some areas have contrasting patterns.
Some areas, primarily in New South Wales, have low diagnosis rates of thin melanoma but high rates of thick melanomas.
This map shows the areas with thin melanomas. As you scroll down, you will see that many of the blue areas (low diagnosis rates of thin melanoma) on this map will turn red in the map for thick melanoma.
Scroll down ↓
3. Areas with higher diagnosis rates tend to have better survival rates.
The areas that tend to have higher diagnosis rates of melanomas typically had better than average survival. The red and orange areas (circled in dotted lines) are those with high diagnosis rates. As you scroll down, you will notice that most of these areas turn blue indicating better than average survival.
Scroll down and notice the areas inside the dotted lines ↓
This phenomenon is presented in the scatter plot below, with each dot representing a small area. Areas with lower diagnosis rates are more likely to also have worse than average survival (lower left corner). Areas with higher than average diagnosis rates are more likely to have better than average survival (upper right corner). The sloping green line shows the overall association.
Since survival from melanoma is better when the melanoma is detected early, this pattern is consistent with higher diagnosis rates including a higher proportion of thin melanomas.
To further explore the geographical patterns of melanoma in Australia:
Why the geographic disparities?
While differences in early detection or improved diagnostic practices may partly explain the geographic variation, researchers from Cancer Council Queensland and Queensland University of Technology suggest that differences in the characteristics of populations in each area are likely to play a more significant role. Read their research article here.
Possible reasons for the geographic disparities
Ethnic mix of the population
Melanoma diagnosis is generally higher among people with European ancestry, and lower among other populations with non-European ancestry. Therefore, the ethnic mix of the population within areas can influence the diagnosis rates in an area.
Access to and use of healthcare
Both the diagnosis and survival depend on access to appropriate and effective healthcare. Access to healthcare varies across different parts of Australia and can be influenced by factors such as the availability of specialist services, travel distance and transport options, and local healthcare infrastructure.
Different levels of UV radiation
While the general pattern is for more northern areas of Australia to have higher UV, local UV readings can vary, and the exposure that individuals get will depend on their own behaviour.
Differences in sun protection behaviours
These can be influenced by the environment. For example, people living near beaches often spend more time outdoors and tend to wear less protective clothing while at the beach. Or, for example, wearing hats is common practice in farming communities, which can protect their face, head, and neck from UV rays.
How can people reduce their risk of melanoma?
Through prevention
Skin cancer is one of the most preventable cancers, and sun and UV protection are key to lowering melanoma risk. Protect yourself from sunburns and UV by practicing the five 'sun‑safe behaviours': slip on protective clothing, slop on sunscreen, slap on a hat, seek shade, and slide on sunglasses. Remember, sun protection from an early age is important.
Living in a low-risk area does not mean you can’t develop melanoma. Having fair skin, light hair and eyes, lots of moles, or a strong family history of melanoma increases your risk. However, melanoma can happen to anyone, no matter their skin colour, culture or genetics.
Did you know the famous singer Bob Marley died of melanoma?
This highlights the fact that people from any cultural or ethnic background can develop melanoma. While certain groups have a higher risk of melanoma, everyone is at some level of risk, so protect yourself from the sun, and checking your skin to see if anything has changed, is important for all Australians.
Through self-check
Most melanomas are first detected by the patients themselves or their partners. Get familiar with your skin by checking your skin regularly. Use a mirror to check hard to see places, like your scalp or back, or get a family member, partner or friend to check for you.
See your doctor if you notice a freckle, mole or lump that is NEW or CHANGING in size, shape or colour; or a sore that does not heal over 4-6 weeks. The earlier the detection and treatment, the better the treatment outcomes. Therefore, value the health of your skin, and do not let anything get in the way of checking your skin and getting it checked by a professional if you see something that is different.
While there is no formal melanoma screening program in Australia, for those who are at higher risk of melanoma should check their skin for irregular or changing lesions, and have regular checks by a medical professional.
What to do when you are diagnosed with melanoma?
While melanoma is common in Australia, for most people the treatment outcomes are very good. Make sure you familiarise yourself with the treatment options you have. This will normally be managed by your general practitioner, but there may be other specialists involved. Find out what other support options there are; the Cancer Council 13 11 20 service can provide you with these details.
The following e‑books are a useful resource for gaining a better understanding of the treatment options for melanoma and other skin cancers.
Call 13 11 20 to get cancer information and support from Cancer Council Queensland.
Cancer Council Queensland, along with the Cancer Councils across Australia, provide a free, confidential telephone support service available to everyone in the country to ensure nobody is left navigating cancer alone. Australians impacted by cancer can call this free service to gain information about cancer, as well as emotional and practical support. Our 13 11 20 hotline can also refer callers to support programs and services in their local area.
Creators of this visual explainer
Dr. Muhammad Haroon. Postdoctoral Fellow Communication Specialist, Cancer Council Queensland.
Project administration, Visualisation, Writing - original draft
Associate Professor Kate Thompson. Lead Digital Learning for Change, Queensland university of Technology.
Methodology, Supervision, Writing - review & editing and Funding acquisition
Professor Peter Baade, Research Lead Cancer Epidemiology, Cancer Council Queensland.
Methodology, Supervision, Writing-review & editing, and Funding acquisition
Distinguished Professor Kerrie Mengersen, Director Centre for Data Science, Queensland University of Technology
Methodology, Funding acquisition
Contributors
Stacey Coke. Clinical Nurse Coordinator, WA Kirkbride Melanoma Advisory Service
Conceptualisation
Dr. Caroline G Watts. Research Fellow, the Sexual Health and Surveillance, Evaluation & Research Programs the Kirby Institute, the University of New South Wales, Sydney
Conceptualisation
Dr. Dilki Jayasinghe. Research Fellow & Affiliate of Centre for Health Services Research Centre for Health Services Research, The university of Queensland
Conceptualisation
Janet Clarke. Senior Advisor (formerly), Prevention and Early Detection, Cancer Council Queensland
Conceptualisation
Sharyn Chin Fat. Senior Manager (formerly), Prevention and Early Detection, Cancer Council Queensland
Conceptualisation
Associate Professor Suzanna Cramb. Principal Research Fellow, Australian Centre for Health Services Innovation, Queensland University of Technology
Conceptualisation
Declaration of conflict of interest
The creators of this visual explainer, Dr. Muhammad Haroon and Professor Peter Baade, are employed by Cancer Council Queensland. Cancer Council Queensland receives income from Cancer Council Australia from the sale of sun protection products including sunscreen. This income is used to fund cancer research, prevention and support activities.
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