Skin Cancer

Skin cancer: the facts

  • 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 9,000 skin cancers and over 900 melanomas diagnosed every year
  • The number of people diagnosed rises each year
  • More men than women are diagnosed with skin cancer
  • Being SunSmart is vital to preventing skin cancer


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What is the skin?

The skin is an organ, like your heart and kidneys. The skin is the biggest organ in the body and does several important jobs such as acting as a barrier and protecting everything inside your body.

The skin is made up of two main layers: the epidermis on the outside and the dermis underneath. New cells are made in the deep layers of the epidermis and are pushed towards the surface.  The epidermis is mainly made up of flat, scale-like cells called squamous cells. These cells make a substance called keratin, a tough, waxy substance that helps to make the skin strong enough to protect the body. At the base of the epidermis are cells called melanocytes which make a pigment called melanin. This pigment gives your skin its colour and protects it from ultraviolet (UV) rays in sunlight. Under the squamous cells are round cells called basal cells. These cells constantly divide to form new keratin-producing cells to replace the ones that wear off the skin’s surface.

Different types of skin cancer

There are different types of skin cancer. The type of skin cancer depends on the skin cells that are affected.

  • If the cells affected are the basal or squamous cells, it is called non-melanoma skin cancer (NMSC)
  • If the melanocytes are affected, it is called melanoma skin cancer


Skin cancer (non-melanoma)

Non-melanoma skin cancer is the most common cancer in Ireland. There are several different types of non-melanoma skin cancer. The most common types are basal cell cancer (BCC) and squamous cell cancer (SCC). Sometimes these cancers are called ’carcinomas.’


Basal cell cancer (BCC)

The most common type of skin cancer, this 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 parts of the face such as the nose, forehead and cheeks. 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 the middle is usually sunken. 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 to another part of the body to form a secondary cancer. It is possible to have more than one basal cell cancer at any one time. Having had one increases your risk of getting another.

Squamous cell cancer (SCC)

This cancer begins in cells called keratinocytes, which are the cells nearest the surface of your skin, lying just above the basal cells. 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.  Rarely, it can develop around your vulva or anus. 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.

Squamous cell skin cancer can look like a crusty, scaly ulcer. Or it may be bumpy and hard and develop into an ulcer. This type of cancer is generally faster growing than basal cell cancer though it does not usually spread.

Risks and causes of skin cancer

  • Sun exposure- Most skin cancers are caused by sun exposure, either long-term, or short periods of intense sun exposure and burning, perhaps while on holiday. Remember even on a cloudy day, UV rays can be strong enough to cause skin damage that can lead to skin cancer
  • Sunbeds- Using sunbeds greatly increases your risk
  • Skin types- People who have fair skin; lots of moles or freckles; or red or fair hair have a greater risk
  • Age- Non-melanoma skin cancers develop very slowly. As you get older you have more time to build up sun damage. However, young people can get skin cancer too
  • Having had skin cancer before– If you have had a non-melanoma skin cancer, you have about a 10 times higher risk of a second non melanoma skin cancer
  • Other skin conditions-People with certain skin conditions or skin treatments can be more likely to develop skin cancer. These include: psoriasis, scarring; solar keratosis; and atopic dermatitis
  • Family history- If someone in your family has had any type of skin cancer, this increases your risk


What skin cancer can look like

  • A spot or sore that does not heal within 4 weeks
  • A spot or sore that itches, hurts, is scabbed or crusty, or bleeds for more than 4 weeks
  • Areas where the skin has broken down (an ulcer) and doesn’t heal within 4 weeks, and you can’t think of a reason for this change

Basal cell skin cancers look like a small, slow growing, shiny, pink or red lump. They can also look like red scaly patches. If left, basal cell skin cancers tend to become crusty, bleed, or develop into an ulcer. They are most common on the face, scalp, ears, hands, shoulders and back.

basal cell

Basal cell 3

Basal cell 2

Pigmented basal 2

 Squamous cell skin cancers are usually pink lumps. They may have hard or scaly skin on the surface. They are often tender, but not always. They can bleed easily and develop into an ulcer. They are most common on the face, neck, lips, ears, hands, shoulders, arms and legs.



Squamous 2

Squamous 3

Squamous scalp

Squamous ear

 These pictures are just a guide and if you are worried about any moles or skin changes it is important to see your GP to get them checked.

All pictures are courtesy of Cancer Research UK. 


What you can do to prevent skin caner

One of the best ways to prevent skin cancer is to be SunSmart

  • Avoid sunburn

Sunburn is a sign that your skin has been damaged by too much UV radiation. Over time this damage can build up and lead to skin cancer. Protect your skin.

  • Avoid the sun and spend time in the shade between 11am and 3pm
  • Wear a T shirt, hat and sunglasses
  • Use sunscreen with at least SPF 15 (the higher the better), with good UVA protection (the more stars the better)


  • Never use sunbeds

Using a sunbed causes skin cancer.  Even one sunbed session can increase your risk of developing squamous cell skin cancer by 67% and basal cell skin cancer by 29%.


  • Apply enough sunscreen

Research shows that most people apply much less than they need to. Apply at least 30ml- about a shotglass full-of sunscreen for each application. Always reapply after changing or swimming- even if your sunscreen is waterproof.

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Checking for skin cancers

Early detection is key to surviving skin cancer. Make a habit of checking your own skin for any changes so you can notice if something changes. If you find any changes, ask your GP to check them.


Diagnosing skin cancer

If you notice a change on your skin that does not heal over 4 weeks and that you cannot explain, visit your GP. He/she may refer you to a skin specialist called a dermatologist who will give you a skin exam where they will look at your skin under a special magnifying glass. The dermatologist or a plastic surgeon may also remove the mole or affected skin, so that the cells can be looked at under a microscope.  This is called a biopsy. During a biopsy, at least 2-5 mm of normal looking skin will be removed as well to ensure that all unusual tissue is removed. A biopsy is usually performed under local anaesthetic.

Depending on what the doctor sees when he or she looks at biopsy tissue under the microscope, you may not need any further treatment. If you do, the doctor will discuss this with you.


Melanoma skin cancer

This type of cancer usually affects the melanin cells in your skin. It is also known as malignant melanoma. It is one of the most common skin cancers and the number of people diagnosed is increasing rapidly each year in Ireland and around the world. In Ireland more women are diagnosed with melanoma but more men die from it.

Watch this video to hear from Irish people who have been affected by melanoma.

Risks and causes of melanoma

  • Ultraviolet light- UV light comes from the sun. Over exposure to sunlight can cause patches of rough, dry skin called solar keratoses, which increases your risk of melanoma by up to 4 times
  • Moles- The more moles you have on your body, the higher your risk of melanoma. You should be very careful about exposing yourself to the sun and should keep an eye on all your moles.
  • Rare birthmarks– a very rare type, called a congenital giant melanocytic naevus, can develop into a melanoma. They are very common on the buttock.
  • Skin colour and freckling– People who are very fair skinned, especially those with fair or red hair; blue, green or grey eyes and those with lots of freckles are more at risk of developing melanoma.
  • Sunburn– People who have had sunburn are twice as likely to get melanoma as those who have not. The risk is higher if you have had sunburn several times in your life.
  • Where you were born- Fair skinned people born in a hot country, for example Australia, have a higher risk than people who went to live in a hot country as a teenager or people with similar skin colouring who live in cooler climates.
  • Sun exposure now and then- People who are exposed to strong sunlight now and then, like holidaying in a hot country, are more at risk of melanoma than people who are continuously exposed to sunlight
  • Sunbeds– Using a sunbed, even just once, increases your risk of melanoma by 20%. Using a sunbed before the age of 35 increases your risk by almost 60%. Never, ever use sunbeds.


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What you can do

Get to know the normal appearance of your skin and any moles you may have. Then, learn your ABCDE’s and check your skin regularly- about once a month. Because melanoma affects both men and women, everyone needs to become aware of their own skin and check themselves.


If you draw a line through a melanoma, the two sides will not match

B- border

The boarder of an early melanoma tend to be uneven. The edges may be scalloped or notched.

C- colour

Most healthy moles are all one colour. A mole with a number of different shades of brown, black or tan is a warning sign. Melanomas may also be blue, red or some other colour

D- diameter

Melanomas are usually larger in size than the rubber at the top of a pencil (¼ inch or 6mm)

E- evolving

Any change- in shape, colour, size, elevation (height), or any other trait, or a new symptom like bleeding, itching or crusting is a warning sign

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What melanoma looks like

Dark mole

The photo below shows a very dark mole. Darkening is one possible sign that a mole is becoming cancerous and could be a melanoma. This mole is about a centimetre across.

Picture of dark mole

 Inflamed mole

The photo below shows a mole that has an area of inflammation around it. The inflamed area is about 7 millimetres at its widest but you can see that the original mole is much smaller than that. Inflammation is another sign that a mole may be developing into a melanoma and needs to be checked out by a doctor.

Picture of inflamed mole

 Melanoma with irregular border

The photo below shows the irregular outline of a melanoma. Normal moles are usually much rounder, with smooth borders.

Picture of an irregular mole

 Melanoma with irregular shape and colour

Below is a very small melanoma. It is only about 4 or 5 millimetres across. But you can see clearly that it is not the same colour throughout. It also has an irregular shape. Irregular colour and shape are signs that should be checked by a doctor.

Picture of a small mole

 Spreading melanoma

The picture below shows clearly a melanoma that is spreading out from a normal mole. If you have a mole that has changed in this way, you should see your doctor as soon as possible.

Picture of a mole spreading

The pictures are just a guide and if you are worried about any moles or skin changes it is important to see your GP to get them checked.


All pictures are courtesy of Cancer Research UK. 

Diagnosing melanoma

If you have a suspicious looking mole, go to your GP. If your GP thinks the mole may be becoming cancerous, you will need to have it removed and looked at under a microscope. This is called an excision biopsy. This is usually done by a specialist skin doctor called a dermatologist.

The dermatologist may use a tool called a dermatoscope to closely examine the abnormal area on your skin.  If the doctor decides that you need to have the mole removed, you will have a local anaesthetic. The doctor then cuts out the whole mole and 2 mm of tissue all around. The tissue is sent to the laboratory for testing. You will need some stiches and the doctor or nurse will tell you how to look after your small wound. 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.

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.

Treatment for melanoma 

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 immunotherapy chemotherapy, radiotherapy, photodynamic therapy and biological therapies.

If you have already been diagnosed with melanoma, you may find it helpful to connect with people who are going through something similar. The Melanoma Support Ireland facebook group offers support and shares experiences. You can find the group by clicking on the button below.

Join Melanoma Support Ireland


Remember Many skin changes may be harmless, but if you notice a new or changing mole, visit your GP without delay. It is never too late to start protecting your skin. Follow the SunSmart code. Look for the UVA logo on your sunscreen bottle. Check your skin using the ABCDE’s. Early detection saves lives.

For a copy of the Marie Keating Foundation’s skin cancer information leaflet, click here.