About skin cancer

Be sun smart and help prevent cancer

How does skin cancer occur?

Skin cancer occurs when skin cells become abnormal. These abnormal cells then develop into a tumour. The tumour grows and develops into a skin cancer.

Nine out of every 10 cases of skin cancer are caused by UV radiation from the sun. This means skin cancer can be prevented.

Limiting your exposure to the sun is just one of the things you can do to reduce your risk of developing cancer
Facts about skin cancer

Most common cancer

Skin cancers are divided into two main types: melanoma and non-melanoma. Non-melanoma skin cancer is the most common cancer in Ireland. There are over 10, 300 non-melanoma skin cancers and over 1,000 melanomas diagnosed in Ireland every year. The number of people diagnosed rises each year.

Being SunSmart is vital to preventing skin cancer.

Early detection is key

Early detection is the key to successful treatment of skin cancer and if you regularly check your skin for damage or changes, it could save your life.

Types of skin cancer

skinThe type of skin cancer depends on the cells in the body that are affected. There are two groups:

  • Non-melanoma skin cancer
  • Melanoma skin cancer.

Non-melanoma skin cancer

The two most common types of non-melanoma skin cancer are:

  • Basal cell carcinoma
  • Squamous cell carcinoma.

Basal cell cancer (BCC)

This cancer develops from basal cells which are in the deepest layer of the epidermis and around the hair follicle. It develops mostly in areas of skin exposed to the sun, including the face. It can also develop on your back, particularly in men, or lower legs. It is most often diagnosed in people of middle or old age.

Basal cell cancer may start as a small lump that gets bigger slowly over months and years. The edges usually have a shiny or pearly look and a sunken middle. Sometimes the middle becomes crusty or an ulcer develops. It usually will not hurt unless knocked but it can be itchy and may bleed if scratched.

It is very rare for basal cell skin cancer to spread. It is possible to have more than one basal cell cancer at any one time.

Squamous cell cancer (SCC)

This cancer begins in cells called keratinocytes, which are the cells lying just above the basal cells on the surface of the skin. Squamous cell cancer most often develops in areas that have been exposed to the sun, including parts of the head, neck, and on the back of your hands and forearms. It can also develop in scars, areas of skin that have been burnt in the past or areas of skin that have been ulcerated for a long time.

Non-melanoma skin cancer tends to appear on the areas of your body that are exposed to the sun – your head, face, arms and legs. You should go to your doctor if you see:

  • A new growth or sore that does not heal in a few weeks
  • A spot or sore that continues to itch, hurt, scab or bleed
  • A skin ulcer that you cannot explain.

Many non-melanoma skin cancers are curable if caught at an early stage.

Melanoma skin cancer

The second group of skin cancer is melanoma. Melanoma skin cancer is quite rare, however, the number of people being diagnosed each year is increasing.

Melanoma is a cancer that begins in the melanocytes. It is also known as ‘malignant melanoma’. Most melanoma cells make melanin, the pigment in your skin, so melanoma tumours are usually brown or black, but can also appear to be pink, tan, or even white.

Melanomas can develop anywhere on the skin, but they are more likely to start on the trunk (chest and back) in men and on the legs in women. They are also common on the neck and face.

Melanoma is less common than basal cell and squamous cell skin cancers, but it is far more dangerous. The number of people affected in Ireland is rising rapidly. Like basal cell and squamous cell cancers, melanoma is almost always curable in its early stages.

Watch our Skintervention video about Irish people affected by melanoma

Limiting your exposure to the sun is just one of the things you can do to reduce your risk of developing cancer
Facts about melanoma

How to check your moles

Limiting your exposure to the sun is just one of the things you can do to reduce your risk of developing cancer
Melanoma is a type of skin cancer that forms in the cells that make melanin. It starts on the normal skin surface and looks like a mole. It is important to diagnose melanoma early. It could save your life.

Remember your alphabet

A: Asymmetrical

Do you have any moles that are not symmetrical – if you drew a line down the middle of the mole would it be the same size and shape on both sides of the line? If your mole is different on either side you should have it checked by your doctor.

B: Border

If the edges around any of your moles are ragged, or uneven, you should show it to your doctor.

C: Colour

If any of your moles change colour, or any mole has a number of different shades of brown, black or tan it is a warning sign and you should show it to your doctor.

D: Diameter

Has the diameter, the size, of your mole got bigger over time. Is it bigger than the top of a pencil (the blunt end)? If so, show it to your doctor.

E: Evolved

Is your mole changing over time? Has it started to bleed, itch or be crusty? If it has, you should show it to your doctor.

Who is at risk of skin cancer?

Sun exposure is the main risk for developing skin cancer. You should take extra care if you have:

  • Fair or freckled skin
  • Fair or red hair
  • Grey, green or blue eyes
  • A large number of moles
  • Have already had skin cancer, or a close family member has already had skin cancer
  • Had radiotherapy
  • Been exposed to chemicals in the workplace.
  • Sustaining five or more sunburns in youth increases the lifetime melanoma risk by 80%. As such,  children are especially at risk


The use of sunbeds dramatically increases the risk of melanoma, especially if you have used them under the age of 30. Using sunbeds is not a safe way to get a tan. You should never use sunbeds.

Just one sunbed session can increase your risk of developing squamous cell skin cancer by 67% and basal cell skin cancer by 29%.  If you have ever used a sunbed your risk of melanoma, the most deadly form of skin cancer, increases by 20%.

Sunbeds do not help to clear up acne. Sunbeds are not a healthy way to prepare your skin for a sun holiday. Sunbeds are not a good way to get Vitamin D. Sunbeds are not a healthy way to tan. If you are using sunbeds, stop immediately before you damage your skin further.

Going to your GP

If you have a suspicious looking mole, go to your GP. If they think the mole may be cancerous, you may need to go to a dermatologist. They may use a tool called a dermatoscope to examine the abnormal area on your skin.

If the mole needs to be removed, you will have an excision biopsy under local anaesthetic. The doctor will cut out the whole mole and 2 mm of tissue all around. The tissue is sent to the laboratory for testing. You will need some stitches.

Follow up will be arranged.

If the mole does not contain any cancerous cells, you will not need any more treatment. If the mole contains any cancerous cells, you may need to have more tests.

Skin cancer treatment

If your mole contained cancerous or precancerous cells, a pathologist will carefully check the biopsy tissue in the laboratory. Your doctor will ask you to go back into hospital for an operation to remove more tissue from around the area of the melanoma. This operation is called a wide local excision.

The main treatment for early and locally advanced melanoma is surgery. Advanced melanoma can also be treated with surgery though treatment will depend on the type and size of the melanoma, where it is found and the organs it affects. Treatments may also include topical chemotherapy or other types of chemotherapy, radiotherapy, photodynamic therapy and biological therapies. Your case will be discussed by a team of medical experts so that the right kind of treatment will be offered to you.