Melanoma skin cancer is the fifth most common cancer in the UK, with around 17,500 new cases and 2,300 deaths every year. Like many other serious health conditions, diagnosing melanoma skin cancer early can make all the difference. In fact, according to experts, over 95% of skin cancers can be treated successfully if diagnosed early enough.
For this reason, knowing the signs and symptoms of skin cancer to look out for is one of the best things you can do to help protect yourself. This is particularly true when it comes to melanoma, which is considered the most dangerous type of skin cancer due to its higher risk of spreading to other areas of the body.
Here, we’ll look closer at melanoma skin cancer and explore five skin changes you shouldn’t ignore.
What is melanoma skin cancer?
The skin is the body’s largest organ. It has several important functions, including protecting internal organs and regulating body temperature. There are two main categories of skin cancer: melanoma skin cancer and non-melanoma skin cancer (including basal cell skin cancer, squamous cell skin cancer, and other rare types).
Melanoma skin cancer begins in cells called melanocytes, which are found in the epidermis (the top layer of skin). It occurs when abnormal cells in the skin start to grow and divide in an uncontrolled way. Melanoma skin cancer can affect any section of skin – for example, in a mole, on a patch of normal skin, or under the nails. However, it’s more common in areas that are more commonly exposed to the sun.
While melanoma skin cancer is less common than non-melanoma skin cancer, it’s considered more dangerous because it’s more likely to spread. Among other things, melanoma cells have specific surface molecules that allow them to attach to blood vessel walls and enter the bloodstream. They also thrive in the challenging environment of the bloodstream and aren’t easily detected by the body’s immune system.
Dr Conal Perrett, consultant dermatologist at The Devonshire Clinic, explains, “Melanoma is the deadliest form of skin cancer, responsible for over 2,000 deaths a year in the UK. Early diagnosis and treatment are important to prevent it from spreading to other organs.
“Whilst new therapies and treatments have significantly improved how we manage patients with melanoma that has spread to other parts of the body, it’s still crucial to identify and diagnose melanoma early before it starts to spread. Once melanoma has spread to other organs, the outcomes for patients are significantly worse. If you are worried about any skin lesions, you should see a consultant dermatologist urgently.”
Note: This article is about melanoma skin cancer. If you’d like to read more about non-melanoma skin cancer, head over to the NHS website.
What causes melanoma skin cancer and are there any risk factors?
Exposure to ultraviolet (UV) light, either from the sun or artificial sources like sunbeds, is the main environmental factor that increases the risk of melanoma skin cancer. UV radiation can lead to changes in DNA that cause skin cells to grow out of control and form melanoma.
According to Cancer Research UK, around 85% of melanoma skin cancer cases are caused by too much UV light. For this reason, taking steps to protect yourself from sun damage is one of the best things you can do to reduce your risk. Check out our article, 11 tips to protect your skin from sun damage, to learn more.
Other risk factors for melanoma skin cancer include…
- Age – the risk of developing melanoma increases with age. Statistics show that, in the UK, around 30% of people diagnosed with melanoma are aged 75 years or above. That said, compared to many other forms of cancer, melanoma is also quite common in younger people.
- Skin type – your skin type and colour can affect your risk of developing melanoma. If you have white skin (especially those with fair or red hair), are prone to sunburn, or have lots of freckles, your risk will be higher. People with black or brown skin can still get melanoma but they have more natural protection against it.
- Moles – The more moles you have on your body, the higher your risk of developing melanoma. One study found that melanoma risk was higher in people who had 100 or more common moles, compared to people with 15 or fewer.
- Birthmarks – most birthmarks, such as common strawberry marks and port wine stains, carry no risk of developing into cancer. However, a very rare type called giant congenital melanocytic naevus can sometimes develop into melanoma if it’s larger than 20cm. Experts recommend checking all birthmarks for any signs of change regularly.
- Genetics and family history – having a close relative who’s had melanoma increases your risk. Research has also linked around 10% of melanoma cases to an inherited gene change.
- Other medical conditions – research has found that medical conditions that weaken the immune system, such as Crohn’s disease, ulcerative colitis, and HIV, can increase the risk of melanoma.
Potential signs of melanoma – 5 skin changes you shouldn’t ignore
New, abnormal moles and changes to existing moles or previously normal patches of skin are the most common symptoms of melanoma skin cancer. As a result, keeping an eye out for any skin changes and speaking to your GP if you’re concerned is one of the best things you can do to protect your health.
It’s important to know what your skin looks like normally, as this makes it easier to notice any unusual changes. For parts of your body that are more difficult to see, consider using a mirror or asking a friend or partner to help.
When checking for signs of melanoma skin cancer, health professionals use the ABCDE test. ABCDE reflects five main categories of change to look out for: asymmetrical, border, colour, diameter, and evolving. These can provide a useful template for checking your skin for signs of cancer. We’ll explore the ABCDE test in more detail below.
Cancer Research UK also has a collection of photographs of abnormal moles, skin patches, and melanomas available on their website if you find visual examples useful.
Note: Melanomas tend to stand out from other moles. If a mole looks very different from others that you have, it’s important to get it checked, even if you don’t have any of the signs listed below.
In rare cases, melanoma can start in the eye – sometimes causing a dark spot to appear in the iris or affecting eyesight. Although melanoma of the eye starts in melanocyte cells, it’s a separate type of cancer from melanoma skin cancer and isn’t linked to sun exposure. You can read more about melanoma of the eye on the Cancer Research UK website.
1. A – asymmetrical
It’s important to pay attention to the shape of a mole or abnormal patch of skin. According to the NHS, normal moles are usually even in shape with two fairly symmetrical halves. Melanomas, on the other hand, may have uneven edges with two differently shaped (asymmetrical) halves.
Dr Conal Perrett, consultant dermatologist at The Devonshire Clinic, says: “Moles that change shape, especially if they become irregular or asymmetrical, may indicate skin cancer. It’s important to monitor moles for any changes in their borders or overall symmetry.”
2. B – border
While normal moles tend to be round with smooth edges, melanomas are more likely to have irregular borders that are blurry or jagged.
3. C – colour
It’s common for melanomas to be uneven in colour. For example, they may contain different shades of black, brown, and pink. Meanwhile, normal moles are usually an even colour – or, if they do contain two colours, these will normally be symmetrical across the two halves.
Dr Perrett says: “A mole that changes its colour or develops multiple colours – such as shades of brown, black, red, white, or blue – should be examined by a healthcare professional. Uneven colouring can be a warning sign.”
4. D - diameter
This refers to the width of a mole or abnormal patch of skin.
According to Cancer Research UK, normal moles are usually small in size, around the size of the end of a pencil or smaller. Meanwhile, most melanomas are more than 6mm wide.
Dr Perrett says: “If you notice a mole increasing in size over a few weeks, it’s important to get it checked. Rapid growth can be a sign of melanoma or other types of skin cancer.”
Note: According to Cancer Research UK, melanomas can be smaller than 6mm wide if diagnosed early.
5. E – evolving
Evolving refers to any changes to moles or abnormal patches of skin. As well as size, shape, and colour changes, other things to look out for include bleeding, itching, moles becoming crusty, or changes in the sensation of a mole or abnormal patch of skin.
Dr Perrett says: “Moles that bleed, become sore, or start to weep fluid are concerning signs and should be evaluated promptly. [Equally] if a mole begins to hurt or becomes itchy, it could signify a change that warrants professional attention. Persistent itching or tenderness in a mole should not be ignored.”
Note: According to Cancer Research UK, most melanomas don’t cause symptoms like pain or itching, and some non-cancerous moles or abnormal patches of skin can be itchy. As a result, these changes don’t necessarily mean you have melanoma – but it’s still important to get checked out.
Signs of melanoma skin cancer in people with brown or black skin
While anyone can develop skin cancer, the NHS highlights that your chances of getting melanoma are lower if you have black or brown skin. People with black or brown skin most often get melanoma on the soles of the feet, palms of the hands (called acral lentiginous melanoma) or under the nails.
However, melanoma can be more difficult to spot on dark skin. According to Cancer Research UK, moles or abnormal patches of skin might…
- Not show any of the ABCD signs
- Be symmetrical
- Be a pink colour
- Appear under a finger or toenail
- Be broken or sore (ulcerated)
- Appear on the palm of your hand or sole of your foot
Final thoughts…
Melanoma skin cancer is one of the most common cancers in the UK, with thousands of new cases diagnosed every year. Despite being less common than other skin cancers, melanoma is considered the most dangerous form of skin cancer because of how quickly it spreads.
For this reason, frequently checking your skin for changes and speaking to your GP if you have any concerns is one of the best things you can do to protect your health.
For further reading, head over to our general health section. Here, you’ll find information on everything from heart and gut health to important health checks for over 50s.
Do you frequently check your skin for changes? Do you have any other tips you’d like to share? We’d be interested to hear from you in the comments below.
