Your expert guide to melanomas and how to spot them

With the news that Sarah Ferguson has been diagnosed with an aggressive form of skin cancer, after previously battling with breast cancer, the condition has been brought to the forefront of the public’s mind once again. 

The duchess underwent a single mastectomy and breast reconstruction last summer. Medics have removed the malignant mole, which came to light when the duchess, 64, had further reconstructive surgery last month.

Her dermatologist had requested that several moles be removed at once and one of them was cancerous. The duchess is now undergoing further checks to make sure the cancer has not spread. 

The duchess is said to have found the diagnosis “distressing”, coming so soon after her breast cancer.   

Her experience demonstrates the importance of keeping an eye on our skin as we get older.

If you have noticed a lingering spot somewhere on your skin, it would be wise not to dismiss it, especially if there’s something unusual about its appearance. Over the past three decades, rates of melanoma skin cancer have more than doubled in the UK, a trend that looks set to continue.

With baking summers starting to become the norm, UK cancer specialists predict there could be 26,500 new cases of melanoma every year by 2038. At present, Cancer Research UK estimates that around 16,700 Brits are diagnosed with melanoma on an annual basis, which works out at around 46 cases per day.

“We’re seeing more cases because people are just travelling a lot more to warmer climates,” says Susanna Daniels, the CEO of UK-based charity Melanoma Focus. “And in recent years we’ve been having these hotter spells in this country.”

“It’s the short, sharp shock of sunburn, which is the highest risk factor, especially in fair-skinned people,” says  Dr Rowland Payne, consultant dermatologist at Devonshire Dermatology, who has had many crowned heads in his consultant rooms.

 “Particularly in people who have a little bit of red colouring, for example, if you have red or auburn hair, then that’s a particularly susceptible colouring for melanoma.”

A friend of the Duchess of York’s commented that this is close to home, as her father had a melanoma when he died, but added: “Sarah is very resilient.”

“There is a slight genetic susceptibility between breast cancer, melanoma and colon cancer. Some patients can have all three conditions in the same family,” says Dr Rowland Payne. 

“It makes sense in such patients to have a colonoscopy, and, in the right age group, mammograms, and to have a total skin examination from time to time.”

According to Cancer Research UK, 86 per cent of all melanoma cases are preventable. Experts like Daniels say that they could be entirely avoided by following sensible precautions such as staying in the shade between 11am and 3pm, and wearing a broad-rimmed sunhat and UV-protected sunglasses.

Suncream needs to be at least factor 30, with a four- or five-star rating. This rating is a measure of how much UVA – ultraviolet rays from the sun, which are capable of penetrating deep into the skin and damaging cells – the suncream is blocking.

“It’s important to reapply suncream, particularly if you’ve been swimming or you’ve been out, because your clothes can rub it off,” says Daniels. “So we recommend that you reapply every couple of hours.”

“The primary thing is prevention of sunburn,” agrees Dr Rowland Payne, “and reporting anything that changes. If your child has many moles, and there’s a family history of melanoma, it might be worth a visit to the dermatologist in the teenage years.”

So what exactly does a melanoma look like, and how does it develop? Read on.

Spotting melanoma

What are the subtypes of melanoma?

There are four main subtypes of melanoma, with superficial spreading melanoma – which starts off by growing along the top layer of the skin – being the most common. According to the Memorial Sloan Kettering Cancer Center, this accounts for 70 per cent of all cases.

The second most common is nodular melanoma, which represents around 15 per cent of cases, and is often described as the most aggressive form of the disease as it grows faster than the other melanoma subtypes. It is more common in over 65s and people of a light complexion and tends to look like a bump or flat lesion which rises above the skin’s surface and is firm to the touch.

Lentigo maligna melanomas accounts for somewhere between 4 and 15 per cent of cases. They usually form on the face, ears or neck of people with sun-damaged skin, often causing a blotchy appearance, and sometimes tend to be confused with more benign skin damage. “They evolve much more slowly than other forms of melanoma,” says Christian Aldridge, a consultant dermatologist, and medical advisor for the charity Melanoma UK. “This presents as an enlarging, asymmetrical lesion with areas of black pigment within brown patches.”

Acral melanoma is the most common melanoma in people of black or Asian ethnicities. It appears on the palms of the hands, soles of the feet or under fingernails or toenails. As a result it is often not spotted until a much later stage. “It’s not easy to see from a patient’s perspective, and due to the delay, it has the worst prognosis of them all,” says Aldridge. It is characterised by a distinct difference in colour to the surrounding skin, and can often be confused for a stain or bruise.  

The most common non-melanoma skin cancer is basal cell carcinoma, a slow-growing skin cancer that does not tend to spread. Other non-melanoma skin cancers such as squamous cell carcinomas and Merkel cell carcinomas are more serious than basal cell carcinoma because they have the ability to spread to the lymph nodes and other organs.

“Non-melanoma skin cancers can appear as non-healing scabs or pinkish skin growths,” says Dr Jenny Nobes, a clinician at private healthcare provider GenesisCare. “While basal cell carcinoma does not tend to be lethal, it does need treatment at an early stage to increase the chances of cure and minimise the cosmetic and functional impact of treatment.”

The treatment for most non-melanoma skin cancers tends to be relatively straightforward. “Just a simple surgery will take care of them,” says Adil Daud, director of melanoma clinical research at the UCSF Helen Diller Family Comprehensive Cancer Center in San Francisco. “You don’t often need to go to systemic treatment with immunotherapy to take care of a basal or squamous cell cancer.”

How does melanoma develop?

Melanoma develops when cells called melanocytes – which produce melanin, the pigment that gives your skin its colour – mutate and start to multiply uncontrollably. In the vast majority of cases, these mutations occur as a consequence of damage from ultraviolet light radiation, but in 1-2 per cent of cases, these mutations have been directly inherited from the individual’s parents at birth.

Melanoma is more common in women under 50 than men, and it remains one of the most common cancer for women of that age group, alongside breast cervix and thyroid. However in later life, the prevalence switches. According to the American Academy of Dermatology, men aged 65 are twice as likely to get melanoma, while men aged 80 are three times as likely to develop the cancer.

Detecting it early before the cancer has spread deeper into the skin is crucial. According to the Cleveland Clinic, melanomas have a 99 per cent cure rate if caught in the earliest stages.

“If primary melanomas are caught early, then patients tend to have very good outcomes,” says Professor Chris Bakal of the Institute of Cancer Research in London. “If it hasn’t spread, and it’s caught at the earliest stage, then cure rates lie between 80 and 100 per cent, usually just by surgery without the need for chemotherapy or immunotherapy.”

What does a melanoma look like?

Jenny Nobes points out that they can range greatly in size, shape, thickness, colour and location on the body, although there are some general trends.

“Classically, melanomas would appear as a dark or pigmented spot on the skin,” says Nobes. “However they can sometimes present as pink, flat areas where the diagnosis is not immediately obvious. They usually occur in sun-exposed skin but can also occur in parts of the body which are usually covered up, as well as under fingernails or toenails and in the eye.”

Susanna Daniels says that overall, men and women tend to get melanomas in different areas. “For men they’re more likely to get them on their trunk, perhaps due to sun damage from walking around with no top on,” she says. “And for women it’s more likely on their legs.”

Melanoma experts refer to what is known as the ABCD rule – where A stands for Asymmetry, B for Border Irregularity, C for Colour and D for Diameter – when it comes to identifying whether a spot or discoloration on the skin might be cancerous.

“If one side is much bigger than the other then that’s asymmetry,” says Daud. “If the border is broken in some places or the colour is very different – either a lot lighter or darker – than the other moles you have on your body, then those are warning signs. Finally when it comes to the size, most moles should not be larger than half a centimetre, like the size of a pencil eraser. If it’s bigger than that, you should probably have it seen by a dermatologist.”

Because early detection is so critical, doctors urge patients to seek medical attention for anything they might be concerned about. “Melanomas normally present as a pigmented brown or black lesion,” says Christian Aldridge. “They start off small and round but with time there is uneven, cancerous growth leading to these ABCD changes. The advice to patients is to report any change. 90 per cent of the time it’s something benign, but we have to cast the net wide in order to catch those melanomas.”

How to tell a mole from melanoma?

According to Aldridge, people should not get too concerned about existing moles on their body turning into something cancerous, as this happens relatively rarely.

“75 per cent of melanomas arise from normal-looking skin, and only 25 per cent arise from a pre-existing mole,” he says.

Harmless moles also stay largely the same in appearance over time and blend in with your normal skin pigmentation. Adil Daud says that whether something is rapidly changing in size is another indication that it might be malignant.

“Moles tend to have a fairly uniform colour and if you look at the ones you have on your body or face, many might have increased over the years, but you shouldn’t see a mole that’s growing month on month,” he says. “If you see something that’s changing over the course of a few months, it’s a sign that it needs to come out.”

You can read more about how to spot dangerous moles in our how-to guide.   

What are the symptoms of skin cancer that has spread?

As melanoma invades deeper into the skin, it begins to ulcerate and bleed. If a lesion or spot on the skin is becoming painful and bleeding, this is one of the warning signs that a melanoma is becoming more advanced.

“The bleeding allows tumour cells to seed into the blood and the skin drainage system known as the lymphatic system,” says Aldridge. “This is serious because melanoma can then spread via two mechanisms – to local lymph nodes or via the blood to any other organ of the body, for example the liver, lungs and the brain.”

Nobes explains that patients who have been diagnosed with skin cancer will receive an examination, sometimes accompanied by scans. “Patients with very thin melanomas – a thickness of less than 1mm – usually have excellent long-term survival with surgery alone,” she says. “The survival rate worsens for patients with very thick melanomas which have spread to local lymph glands.”

Patients with thicker melanomas, often referred to as Stage 2 melanoma, will receive a small operation known as a sentinel lymph node biopsy, where a lymph node is removed for analysis to help assess the spread.

Aldridge explains that melanoma treatments have improved markedly over the past 15 years, with molecular testing enabling doctors to identify genetic mutations in the melanoma which make it susceptible for targeted therapies. As a result, immunotherapies are now being used to treat Stage 2 melanomas which have not yet metastasised or spread to other organs.

Stage 3 and 4 melanomas are cases where the cancer has spread to multiple organs. Bakal explains that the symptoms will depend heavily on where the melanoma has ended up. “When metastatic cells move to other parts of the body, they’re invading those tissues and shutting down their function,” he says. “So if they reach the liver, it will stop working, or if they reach the brain, the patient will have neurological symptoms.”

The current five-year survival rates for stage 3 melanoma are 70 per cent, and 30 per cent for stage 4 melanoma, although both are improving all the time with advances in treatments. The drugs which have made the biggest differences are forms of immunotherapy called checkpoint inhibitors, as well as BRAF and MEK inhibitors which target particular genetic forms of the disease. These drugs all act to shrink the tumours and can keep them under control for long periods of time.

In years to come, further improvements are likely, for example through personalised cancer vaccines which use a technology called messenger RNA. This can be used to deliver a treatment which has been cultivated based on the exact genetic code of that patient’s tumour. Moderna and Merck currently have a personalised cancer vaccine in clinical trials for advanced melanoma patients.

“I’ve been working in this field for 15 years and we’ve gone from a time when somebody with metastatic melanoma had maybe six to nine months of survival time, to an average of six to seven years,” says Adil Daud. “That’s an enormous difference.”

Can I cut my risk?

As well as staying out of the sun, there is also some emerging evidence that taking vitamin D supplements may help reduce your risk of melanoma. Earlier this year, a Finnish study showed that adults at a higher risk of skin cancer who took vitamin D tablets, were less likely to get the disease.

“Being deficient in vitamin D has been associated with thicker melanomas at diagnosis, and people are also more likely to suffer a recurrence of their cancer,” says Susanna Daniels. “We suggest taking the recommended dose, which is 10 micrograms of vitamin D supplements a day.”

For people with either a family history of melanoma, a fair skin tone or past use of indoor sunbeds, it is especially important to be vigilant.