What is skin cancer?
Skin cancer is one of the most common types of cancer, most commonly caused by over-exposure to the sun's ultraviolet (UV) rays. If you have light-coloured skin, have had frequent sunburn or spend a lot of time in strong sunlight, your risk of skin cancer may be higher. Repeated sunburn can damage skin cells, and can cause them to start dividing or growing uncontrollably.
Skin cancer is usually grouped as non-melanoma skin cancer or melanoma. Non-melanomas are the most common, and include basal cell carcinoma and squamous cell carcinoma. Melanoma is a less common but more dangerous type of skin cancer.
Skin cancer is usually diagnosed after the age of 40, and often much later. It’s relatively uncommon in children and teenagers.
The World Health Organisation advises against sunbathing and classifies all kinds of UV radiation as carcinogenic in the highest risk category. According to the WHO, 4 out of 5 cases of skin cancer are preventable by avoiding UV rays.
Skin cancer symptoms
Skin cancer can vary in appearance and can occur anywhere on the body, but most often occur in skin that is especially exposed to the sun.
Skin changes that could be a sign of skin cancer include:
Scabby, rough, red, flaky skin that will not heal (or heals and comes back)
Skin-coloured or pale red spots or lumps that can also flake, itch and be sore
New pigment spots, age spots, birthmarks or moles that have irregular borders or change colour (sometimes with white, red or blue colouring)
Old pigment spots, age spots, birthmarks or moles that change colour or shape, grow or bleed
What else might cause the skin to change?
Dry skin, eczema and psoriasis can cause skin changes that look like skin cancer. Ringworm, rosacea, warts, athlete's foot and nail fungus can also resemble cancerous abnormalities. Lumps in the skin that grow, particularly in older people, are often simply benign skin abnormalities that are not malignant.
In very rare cases, skin changes can be a sign of a serious underlying disease. Cancers like lymphoma and lymphatic leukaemia, for example, can sometimes cause skin abnormalities and skin tumours.
Causes of skin cancer
Skin cancer involves the skin cells starting to divide in an uncontrolled manner, forming cancer cells. It can be caused by sunburn, which the cells fail to repair, for instance.
If you’re often sunburnt, you increase the risk of serious skin abnormalities that lead to skin cancer. But the skin can also develop tumours from a combined amount of sun exposure you’ve had throughout your life. People with light skin or large birthmarks or moles are more vulnerable to cancer than others, and the risk of being affected increases with age.
The sun's ultraviolet rays are the most common cause of cell changes and skin cancer. But there are exceptions – certain skin cancers can occur in skin that has not been exposed to the sun.
Factors that increase the risk of skin cancer:
Over-exposure to UV radiation, including artificial sunlight in a tanning bed
Having fair skin
Having many or large birthmarks or moles
Previous sunburn or other burns
Chronic wounds or sores
Various diseases, including other forms of cancer
Certain treatments and therapies, including radiation therapy and drugs that weaken the immune system
Types of skin cancer
Basal cell carcinoma (BCC)
Basal cell carcinoma belongs to the non-melanoma group. It’s easily the most common type of skin cancer, making up around three-quarters of skin cancers. This type of cancer usually appears as an external skin abnormality, like a smooth, skin-coloured spot or lump.
It can also appear as an eczema-like sore that will not heal, or that heals and then comes back again. It typically grows slowly and very rarely spreads to other parts of the body.
Basal cell carcinoma is often caused by prolonged exposure to the sun, but genetic factors can also play a role. It mostly affects people with fair skin in the areas with the most sun exposure, like the face, neck, chest, stomach or back.
Basal cell carcinoma can appear in a few different ways:
Surface basal cell carcinoma – Usually appears as a flaky, eczema-like patch
Nodular or lump-shaped basal cell carcinoma – Initially resembles a spot or lump, and can grow into wart-like lump. It may have a raised border with an open wound or small blood vessels in the centre
Aggressive basal cell carcinoma – Grows deeper into the skin and can resemble a scar or flat, white or yellow/pink skin abnormality that can develop into an ulcer.
Squamous cell cancer (SCC)
Squamous cell cancer makes up around 20% of skin cancers. It often grows deeper than basal cell carcinoma and in rare cases, it may spread to nearby lymph nodes.
It’s usually a result of prolonged exposure to the sun and is most common in people with fair skin. Squamous cell cancer typically appears on the face, crown, neck or hands. It can resemble a wart-like, skin-coloured or pale red lump, or eczema that won’t heal. Spots and lumps can be sore, flaky or ulcer-like.
Squamous cell cancer can develop from actinic keratosis – dry patches of skin that have been damaged by the sun. Red, scaly patches of skin caused by Bowen's Disease can also lead to squamous cell cancer. It can also occur in scars or unhealed wounds.
Melanoma is the rarest and most serious form of skin cancer, which, in some cases, can spread rapidly in the body. It's therefore important to treat melanoma as early as possible.
A new mole or a change to an old mole is often the first sign of melanoma. The mole may be brown or black, but can also have shades of white, red or blue. The mole might grow in size, develop an irregular shape, or bleed. They will often appear on skin exposed to the sun, like the chest, stomach, back, arms or legs.
Melanoma is caused by a mutation in your melanocytes, the skin cells that produce the melanin which gives your skin its pigment. The risk of melanoma increases with the number of sunburns you’ve had between ages 15-20. But it can also appear in skin that has never been exposed to the sun, like the soles of the feet, palms of the hands, in the mouth, or groin.
There are a few different types of melanoma:
Superficial spreading melanoma – The most common form of malignant melanoma, often resembling a brown or black, flat or slightly raised spot that may grow within the skin's outer layer for months or years before spreading deeper into the skin
Nodular melanoma – The second most common form of malignant melanoma, which often resembles a black or blue lump that grows quickly. It can expand deeper into the skin if it’s not removed
Lentigo maligna melanoma – A less common, slower-growing form of melanoma, which may look like a freckle. Over years, it may grow into a dark lump and expand deeper into the skin
Acral lentiginous melanoma – A rare type of melanoma that isn’t caused by UV radiation. It can be found under a nail, on the soles of the feet, toes, fingers or palm, and may be confused with athlete's foot or nail fungus
Amelanotic melanoma – A colourless or light pink, brown or grey-coloured melanoma
Diagnosis and treatment
In many cases, a visual and/or physical examination by a doctor is enough to diagnose changes in the skin. A skin biopsy might occasionally be needed to check whether a skin abnormality is dangerous or malignant. If skin cancer is suspected, the lymph nodes may also be checked. An examination could also involve using X-rays to show if cancer has spread in the body.
Once skin cancer is diagnosed, further treatment is needed. Depending on the type of skin cancer, early stages of skin cancer can sometimes be treated with a prescription cream that boosts the immune system. Freezing (cryotherapy) and laser treatment are other common alternatives. Surgery to remove the cancerous skin and the tissue around it is also common.
Skin cancer is often curable with the right treatment. Starting treatment right away is crucial to prevent the cancer from spreading throughout the body. Squamous cell cancer or malignant melanoma that have spread to other parts of the body may need surgery and treatment like immunotherapy or chemotherapy.
What can I do myself?
Protecting yourself from the sun is the best way to prevent getting skin cancer in the first place. Here are some simple steps everyone can take:
Spend less time in the sun – Avoid staying out too long in strong sunlight, especially if you have light skin, large birthmarks or moles or there is a history of malignant melanoma in the family
Adjust the time you spend in the sun according to where you are – Reflection from the snow, water and light beaches means you can burn faster, and the sun is stronger the closer you get to the equator
Protect your skin and head – Apply high protection factor sun cream to protect yourself against UVA and UVB radiation, wear sunglasses, a cap or hat, and protect your skin with clothes if the sun is very strong
Stay in the shade – During the middle of the day when the sun's rays are at their strongest, stay out of the sun altogether, to minimise the risk of sunburn.
You should also check your skin regularly for signs of any changes. Pay attention to areas that get a lot of sun exposure, as well as those that don’t, such as the scalp and soles of your feet. Look for anything unusual, like eczema-like patches, lumps in the skin, or moles that have grown, turned an unusual shape or colour, or are bleeding. A raised birthmark or mole or a pigment patch that is hard may also need further examination.
Use the ABCDE method to check out moles:
Asymmetry – Is one half of the mole shaped differently than the other?
Border – Is the border with the surrounding skin irregular or blurry?
Colour – Is the mole an even colour or does it have multiple hues?
Diameter – Is the mole bigger than 5 millimetres?
Evolution – Has the mole changed over time at all, including in size, shape, colour or height?
Pay special attention to any skin spots that look different to your other birthmarks or moles.
When to seek medical help
See a doctor if you have a birthmark, mole or age spot that itches, develops into an ulcer or bleeds, has an irregular colour or shape, or is bigger than 5 millimetres in diameter. You should also seek help if you’ve got an eczema-like patch that won’t heal.
How Livi can help
You can contact Livi for advice and information if you suspect skin cancer. A doctor will make an individual assessment based on your symptoms and the results of a consultation. You may then be given a prescription for treatment, or referred for specialist care.
- Reviewed by:
- Dr Rhianna McClymont, Lead GP at Livi