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Introduction Skin cancer is common. There are three main kinds: basal cell carcinoma, often known as a rodent ulcer; squamous cell carcinoma; and; malignant melanoma. Fortunately, the commonest kind is the least dangerous, and the most dangerous kind, malignant melanoma, is the least common. Skin cancer is very rare in children but is more common as people get older. The numbers of skin cancers rise with age because the main cause of all types of skin cancers is sunlight exposure. Sunlight contains ultraviolet light (UV), and this is what does the harm, particularly to the skin of babies and young children. The numbers of skin cancers vary from country to country. In tropical countries with large white populations, the numbers are proportional to the amount of sunlight. Australia, South Africa and the Southern American states all have a very high incidence of skin cancer in their white populations. People with black skin (for example, people of African or Caribbean descent) are better protected by their skin colouring.
Symptoms Rodent ulcer (basal cell carcinoma) is one of the commonest of all cancers and one of the least dangerous. It affects the skin, mainly in areas exposed to the sun, and especially on the nose and around the eyes. It is a slowly growing, raised-edged swelling with a dimple in the centre. Small blood vessels are often visible just below the surface. It hardly ever spreads to other parts of the body, although it can do so if neglected. It can then cause a lot of tissue damage, especially by burrowing deep into the tissues (hence the name rodent ulcer). Squamous cell carcinoma is a skin cancer also related to sunlight exposure. It starts as a small, firm, painless lump occurring most often on the lip, ear or back of the hand. It enlarges fairly rapidly and then will often break down in the centre to form a crater. This is called ulceration. It can spread to the lymph nodes and from there to various parts of the body. Be very suspicious of anything like this on your lip.
Causes The cause of skin cancer is excessive exposure to sunlight.
Diagnosis The diagnosis of both rodent ulcer and squamous cell carcinoma is usually made by examination under the microscope of the tumour (lump) after it has been fully removed. Treatment Rodent ulcer can be treated by direct surgical removal, by radiation or by freezing. The method advised is likely to depend on whether you are seen by a surgeon or by a dermatologist. All methods are equally effective. Squamous cell carcinoma must be removed surgically as early as possible. Unlike the rodent ulcer, this tumour may spread to other parts of the body and this can lead to death.
Prevention The best way to protect yourself from skin cancer is to take care in the sun: Don't wait till your skin feels uncomfortable before taking preventative action. The best form of protection is defence.Once your skin is burned the damage has already been done so cover-up up with loose-fitting clothes. Make sure that your legs and arms are covered. Tightly woven fabrics will provide the best protection from the sun. Avoid direct exposure to sunlight between the hours of 11am and 3pm when the sun is at its strongest. If you do go outside between these times cover-up with clothes, hat and sunglasses and apply plenty of sun protection lotion. Always use a sun protection lotion with an SPF (sun protection factor) of at least 15. Very fair-skinned people and children need to use lotions with an SPF of up to 40.
The skin is damaged most by the sun before the age of 18. Make sure that your entire body is covered by sun protection lotion.This includes your face, hands, feet and neck. The most vulnerable parts of your body are the places that are not usually exposed to sunlight. Apply sun lotion at least 30 minutes before going out in the sun. Reapply it every couple of hours, as sweat and friction against towels for example will cause it to wear off. Reapply immediately after swimming, even if your lotion is a waterproof variety. Wear waterproof sun protection when swimming. UVA and UVB rays can penetrate through a metre or so of water. Cloud and fog do not protect skin from ultraviolet rays. Cover up with clothing and use SPF 15 sun lotion even on cloudy days. Always wear a hat and sunglasses that have UVA and UVB filters when in the sun. Ultraviolet rays can damage the retinas in your eyes causing cataracts.
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