What is skin cancer?

Skin cancer is a disease in which abnormal cells grow uncontrollably in the outer layers of your skin. Your skin acts as a protective shield against heat, light, infection, and injury. But it will only take limited punishment.

There are three main types of skin cancer:

• Basal cell carcinomas are easily treated and rarely fatal. They usually appear as raised, translucent lumps. Some people describe them as pearly in appearance.
• Squamous cell carcinomas are also unlikely to lead to death. They sometimes appear as nodules or as red, scaly patches.
• Malignant melanoma is the least common, but most aggressive form of skin cancer. It is generally irregular in shape, sometimes in or around a mole, and has a black, tan or brown shading. Early treatment is vital as it accounts for the vast majority of deaths from skin cancer.

What causes skin cancer?

Skin cancer is more common in people with light coloured skin who have spent a lot of time in the sun. It can appear anywhere on your body, but it is most likely to occur on those areas that have been exposed to more sunlight, such as your face, neck, and arms.

A combination of factors will determine whether you get skin cancer. People with a history of the disease in the family are probably at greater risk. Altitude and cloud cover will affect the sun's intensity. Its rays are most intense on the equator, but recent concern has centred on countries in the extreme south and north where ozone depletion allows greater penetration of ultra violet wavelengths. That said, the sunshine over the UK is more than capable of triggering a skin cancer.

What treatments are available?

Like many other types of cancer, a range of treatments is available. These include surgery to cut out the cancer - this is frequently done with a laser - chemotherapy and radiation therapy. These are the more standard treatments, but cancer research is hopeful that new techniques will soon be widely available, such as:

• Immunotherapy involves boosting the body's natural defences to kill the cancer;
• Photochemotherapy uses a laser to activate a potent anti-cancer drug that has been absorbed directly into cancer cells.

How do you minimise the risks?

You should avoid being in strong sunlight for long periods - especially around midday. A factor-15 sunscreen should be applied to exposed areas of skin. It is always best to cover up with clothing - hats should provide shade for both the face and back of the neck. Most experts advise people not to use sunlamps or tanning parlours: a tanned skin is damaged skin.