Skin cancer develops when cells within the skin stop growing and dividing as normal and instead, grow out of control. They grow and divide at an uncontrolled rate and form a lump or tumour within the skin.
This is a common type of cancer although it is easy to treat and has a high success rate. The only exception is malignant melanoma which is hard to treat unless caught at an early stage.
Two types of tumours
This tumour is either benign or malignant. A benign tumour does not invade other areas of the body. But a malignant tumour is an aggressive form of growth which invades tissues and other parts of the body.
A malignant tumour is considered to be cancerous. A malignant tumour can spread to other organs to form ‘secondaries’. This is known as metastasis which can be life threatening.
Types of skin cancer
There are 3 types of skin cancer which are:
- Squamous cell carcinoma
- Basal cell carcinoma
- Malignant melanoma
Basal cell carcinoma is a slow growing form of cancer which develops in the epidermis (outer layer of skin). It develops on all areas of the skin which are exposed to the sun.
Find out more in our basal cell carcinoma section.
Squamous cell carcinoma also develops in the top layer of skin but involves a different type of skin cell. It mostly affects the face and causes the development of a hard, scaly ulcer which fails to heal.
Find out more in our squamous cell carcinoma section.
Malignant melanoma is the most serious form of skin cancer which develops in a mole and causes it to change shape, colour or size. This form of skin cancer is potentially fatal and must be seen as soon as possible by your GP.
Find out more in our melanoma section.
Causes of skin cancer
All forms of skin cancer are caused by excessive exposure to the sun which is a particular risk for people with fair or very white skins. Prolonged exposure to sunlight can cause burning and/or a tan which may seem desirable but is a sign of skin damage.
Ultraviolet (UV) A and B rays are responsible for this change to your skin colour but it can cause changes to damage to the skin cells which then trigger cancer.
Skin cancer develops differently between men and women: men develop this on their shoulders and back whereas women get these on their arms and legs.
People with a dark skin are at a lower risk of skin cancer.
Symptoms of skin cancer
This depends upon what type of skin cancer you have. Basal cell carcinoma presents as a pinky-brown lump with a smooth surface. Squamous cell carcinoma is characterised by an area of thick, scaly skin which later develops into a red-brown lump. Melanoma develops in a mole which changes in a variety of ways, e.g. increase in size, itches, bleeds or changes colour.
Diagnosing skin cancer
Your GP will diagnose skin cancer after examining the affected area of skin. You may be referred for further investigations such as a skin biopsy, blood tests and x-rays/scans.
Treatment for skin cancer
Benign skin cancer is treated by surgical removal of the infected area of skin, usually under a local anaesthetic. Another option is cryosurgery where the offending lump is frozen with liquid nitrogen which causes it to shrink and fall off.
Photodynamic therapy is based upon high frequencies of light which are targeted at the tumour. This extreme intensity destroys the tumour.
Melanoma is also treated with surgery but additional forms of treatment such as chemotherapy may be required.
Preventing skin cancer
Excessive skin exposure is the main culprit so cover up in hot weather, apply a suncream with a high sun protection factor (SPF) and avoid tanning salons. Wear loose clothing and a hat.
Check any spots or moles you have on a regular basis. Get into the habit of doing this. If you notice any changes then visit your GP.