Skin cancer facts for kids

Skin cancer is the term that is used for all bad forms of growth of the skin. In everyday use, people often talk about melanoma, but there are other forms of skin cancer, too. These are usually named after the type of cell that grows uncontrollably. Most skin cancers develop in the epidermis. Very often a tumor can be seen, so it is often possible to detect skin cancer at an early stage. Very few people with skin cancer will die of the disease., though it can be disfiguring. Melanoma survival rates are poorer than for non-melanoma skin cancer, although when melanoma is diagnosed at an early stage, treatment is easier and more people survive.

Skin cancer is the most commonly diagnosed type of cancer. Melanoma and non-melanoma skin cancers combined are more common than lung, breast, colorectal, and prostate cancer. Melanoma is less common than both basal cell carcinoma and squamous cell carcinoma, but it is the most serious — for example, in the UK there were over 11,700 new cases of melanoma in 2008, and over 2,000 deaths. It is the second most common cancer in young adults aged 15–34 in the UK. Most cases are caused by over-exposure to UV rays from the sun or sunbeds.

Non-melanoma skin cancers are the most common skin cancers. The majority of these are basal cell carcinomas. These are usually small spot growths caused by too much exposure to the sun over time. They do not usually spread, and rarely kill.

Types

Signs and symptoms

There are a variety of different skin cancer symptoms. These include changes in the skin that do not heal, ulcering in the skin, discolored skin, and changes in existing moles, such as jagged edges to the mole, enlargement of the mole, changes in color, the way it feels or if it bleeds. Other common signs of skin cancer can be painful lesion that itches or burns and large brownish spot with darker speckles.

Causes

Ultraviolet radiation from sun exposure is the primary environmental cause of skin cancer. This can occur in professions such as farming. Other risk factors that play a role include:

• Light skin color
• Age
• Smoking tobacco
• HPV infections increase the risk of squamous-cell skin cancer.
• Some genetic syndromes including congenital melanocytic nevi syndrome which is characterized by the presence of nevi (birthmarks or moles) of varying size which are either present at birth, or appear within 6 months of birth. Nevi larger than 20 mm (3/4") in size are at higher risk for becoming cancerous.
• Chronic non-healing wounds. These are called Marjolin's ulcers based on their appearance, and can develop into squamous-cell skin cancer.
• Ionizing radiation such as X-rays, environmental carcinogens, and artificial UV radiation (e.g. tanning beds). It is believed that tanning beds are the cause of hundreds of thousands of basal and squamous-cell skin cancer. The World Health Organization now places people who use artificial tanning beds in its highest risk category for skin cancer.
• Alcohol consumption, specifically excessive drinking increase the risk of sunburns.
• The use of many immunosuppressive medications increases the risk of skin cancer. Cyclosporin A, a calcineurin inhibitor for example increases the risk approximately 200 times, and azathioprine about 60 times.
• Deliberate exposure of sensitive skin not normally exposed to sunlight during alternative wellness behaviors such as perineum sunning.

Prevention

Sunscreen is effective and thus recommended to prevent melanoma and squamous-cell carcinoma. There is little evidence that it is effective in preventing basal-cell carcinoma. Other advice to reduce rates of skin cancer includes avoiding sunburn, wearing protective clothing, sunglasses and hats, and attempting to avoid sun exposure or periods of peak exposure. The U.S. Preventive Services Task Force recommends that people between 9 and 25 years of age be advised to avoid ultraviolet light.

The risk of developing skin cancer can be reduced through a number of measures including decreasing indoor tanning and mid-day sun exposure, increasing the use of sunscreen, and avoiding the use of tobacco products.

It is important to limit sun exposure and to avoid tanning beds, because they both involve UV light. UV light is known to damage skin cells by mutating their DNA. The mutated DNA can cause tumors and other growths to form on the skin. Further, there are other risk factors beside just UV exposure. Fair skin, prolonged history of sunburns, moles, and family history of skin cancer are just a few.

There is insufficient evidence either for or against screening for skin cancers. Vitamin supplements and antioxidant supplements have not been found to have an effect in prevention. Evidence for reducing melanoma risk from dietary measures is tentative, with some supportive epidemiological evidence, but no clinical trials.

Zinc oxide and titanium oxide are often used in sunscreen to provide broad protection from UVA and UVB ranges.

Eating certain foods may decrease the risk of sunburns but this is much less than the protection provided by sunscreen.

A meta-analysis of skin cancer prevention in high risk individuals found evidence that topical application of T4N5 liposome lotion reduced the rate of appearance of basal cell carcinomas in people with xeroderma pigmentosum, and that acitretin taken by mouth may have a skin protective benefit in people following kidney transplant.

A paper published in January 2022 showed that a vaccine that stimulates the production of a protein critical to the skin's antioxidant network could reinforce people's defenses against skin cancer.

Epidemiology

Age-standardized death from melanoma and other skin cancers per 100,000 inhabitants in 2004

no data      <0.7      0.7–1.4      1.4–2.1      2.1–2.8      2.8–3.5      3.5–4.2

4.2–4.9      4.9–5.6      5.6–6.3      6.3–7      7–7.7      >7.7

Skin cancers result in 80,000 deaths a year as of 2010, 49,000 of which are due to melanoma and 31,000 of which are due to non-melanoma skin cancers. This is up from 51,000 in 1990.

More than 3.5 million cases of skin cancer are diagnosed annually in the United States, which makes it the most common form of cancer in that country. One in five Americans will develop skin cancer at some point of their lives. The most common form of skin cancer is basal-cell carcinoma, followed by squamous cell carcinoma. Unlike for other cancers, there exists no basal and squamous cell skin cancers registry in the United States.

Images for kids

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  Micrograph of melanoma, fine-needle aspiration (FNA), field stain

See also

In Spanish: Cáncer de piel para niños