A risk factor is anything that increases a person's chance of developing cancer. Some risk factors can be controlled, such as smoking, and some cannot be controlled, such as age and family history. Although risk factors can influence the development of cancer, most do not directly cause cancer. Some people with several risk factors never develop cancer, while others with no known risk factors do. However, knowing your risk factors and communicating them to your doctor may help you make more informed lifestyle and health-care choices.

The following factors can raise a person’s risk of developing skin cancer:

Exposure to sunlight/UV radiation. Ultraviolet B (UVB) radiation causes sunburn and plays a role in the development of basal and squamous cell cancers. Ultraviolet A (UVA) penetrates the skin more deeply and contributes to photoaging (premature aging of the skin) or wrinkling. The role of UVA in the development of non-melanoma skin cancer is suspected, but not yet certain. People who live in areas with year-round, bright sunlight (which includes both UVA and UVB) or at high altitudes have a higher risk of developing skin cancer, as do those who spend significant time outside or on a tanning bed (which emits mostly UVA).

Fair skin. Less pigment (melanin) in skin offers poorer protection against UV radiation. People with light hair and light-colored eyes who have skin that tans poorly or freckles, or those who burn easily, are more likely to develop skin cancer.

Gender. Rates of skin cancer in white males have increased in recent years.

Age. Most basal cell and squamous cell cancers appear after age 50, but cancers may appear earlier in individuals with sun-damaged skin.

A history of sunburns or fragile skin. Skin that has been burned, sunburned, or injured from disease is at higher risk for skin cancer. Squamous cell and basal cell cancers occur more often in people with higher lifetime exposure to the sun or other sources of UV radiation.

Individual history. People with weakened immune systems or those who use certain medications (such as immunosuppressive drugs, certain steroids, and drugs that make the skin sensitive to light) are at higher risk for developing skin cancer, particularly squamous cell cancers. People with very rare predisposing genetic conditions, such as xeroderma pigmentosum, nevoid basal cell carcinoma syndrome, or albinism are at much higher risk for developing skin cancer.

Previous skin cancer. People who have had any form of skin cancer are at a higher risk for developing another skin cancer. Thirty-five percent (35%) to 50% of people diagnosed with one basal cell cancer will develop a new skin cancer within five years. Thus, people who have had one skin cancer need ongoing, follow-up care to watch for additional cancers.

Precancerous skin conditions. Two types of lesions, known as actinic keratoses, characterized by rough, red or brown scaly patches on the skin, or Bowen's disease, are usually more common in areas exposed to the sun. Such areas can change into squamous cell cancers in some people. Bowen's disease in non-sun-exposed areas may be related to arsenic exposure. Use of sunscreens may decrease the risk of actinic keratoses.

Viral infection. People infected with a specific type of human papillomavirus (HPV) are at increased risk for developing squamous cell carcinoma, particularly if their immune system becomes suppressed.

Prevention

Reducing exposure to sunlight and other sources of UV radiation lowers the risk of skin cancer. This is important for all age groups, but is especially important for people who have risk factors for skin cancer. Sun damage is cumulative, meaning it builds up over time. Steps to reduce exposure and help prevent many cases of skin cancer include:

• Preventing sunburn
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• Limiting or avoiding sun exposure between 10:00 AM and 4:00 PM
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• Wearing sun-protective clothing and a hat that shades the face, neck, and ears. Clothes made of fabric labeled with UPF (UV protection factor) may provide better protection. UV-protective sunglasses are also recommended.
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• Using sunscreen with a sun protection factor (SPF) of 15 or higher throughout the year and reapplying it often, especially after heavy perspiration or being in the water
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• Examining skin regularly (examinations by a health-care professional and self-examinations)
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• Avoiding use of sun lamps, tanning beds or tanning salons