Skin Cancer (Non-Melanoma): Risk Factors and Prevention

Approved by the Cancer.Net Editorial Board, 01/2018

ON THIS PAGE: You will find out more about the factors that increase the chance of developing this type of cancer. Use the menu to see other pages.

A risk factor is anything that increases a person’s chance of developing cancer. 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. Knowing your risk factors and talking about them with your doctor may help you make more informed lifestyle and health care choices.

The following factors may raise a person’s risk of developing non-melanoma skin cancer/keratinocyte carcinoma: 

  • Sun exposure. Exposure to ultraviolet (UV) radiation from the sun plays a major role in the development of skin cancer. People who live at high altitudes or in areas with bright sunlight year-round have a higher risk of developing skin cancer. People who spend a lot of time outside during the midday hours also have a higher risk. Recreational suntanning should be avoided to reduce the risk of skin cancer.

    Exposure to ultraviolet type B (UVB) radiation appears to be more closely linked with skin cancer, but newer research suggests that ultraviolet type A (UVA) may also play a role in the development of basal cell carcinoma, squamous cell carcinoma, and melanoma. UVB radiation causes sunburn and does not penetrate car windows or other types of glass. However, UVA can pass through glass and may cause aging and wrinkling of the skin in addition to skin cancer. Therefore, it is important to protect your skin from both UVA and UVB radiation (see “Prevention” below).

    Because Merkel cell cancer often occurs on the sun-exposed areas of the head and neck, many doctors think that sun exposure may also be a risk factor for this type of cancer.

  • Artificial tanning. People who use tanning beds, tanning parlors, or sun lamps have an increased risk of developing all types of skin cancer. There is no safe amount of indoor tanning. Any use of indoor tanning devices increases the risk of skin cancer, including melanoma, and this risk increases with more use of indoor tanning. 

  • Fair skin. People with a fair complexion, blond or red hair, blue eyes, and freckles are at increased risk for developing skin cancer. People whose skin has a tendency to burn rather than tan also have an increased risk. Despite this, all people, regardless of skin color, are at risk for developing skin cancer.

  • Race/ethnicity. White people are most likely to develop Merkel cell cancer; however, some black people and people of Polynesian descent develop the disease.

  • Merkel cell polyomavirus (MCV). Research indicates that there is a link between this virus and Merkel cell cancer. MCV is present in up to an estimated 80% of Merkel cell cancers. However, scientists believe MCV is common, while Merkel cell cancer is not. More research is needed to learn the role of MCV in this connection.

  • Precancerous skin conditions. Rough, red, or brown scaly patches on the skin, called actinic keratoses or Bowen's disease, are usually more common in areas exposed to the sun. These areas can change into squamous cell cancers in a small number of people. The more actinic keratoses a person has, the higher the risk that he or she will develop a squamous cell carcinoma. Using a broad-spectrum sunscreen throughout the year that protects against both UVA and UVB radiation and has a sun protection factor (SPF) of 30 or more helps decrease the risk of developing actinic keratoses. See the Prevention section below for more information about protecting your skin from the sun.

  • Gender. The number of older white men and younger white women who have developed skin cancer in recent years has increased. Men are also more likely to develop Merkel cell cancer.

  • Age. Most basal cell and squamous cell carcinomas typically appear after age 50. However, in recent years, the number of skin cancers in people age 65 and older has increased dramatically, although this may be due to better screening and patient tracking efforts in skin cancer. Younger people can also develop non-melanoma skin cancer, especially if they have fair skin, an inherited (genetic) syndrome that puts them at high risk, or been exposed to significant amounts of radiation or UV radiation from the sun. Merkel cell cancer is most common in people older than age 70.

  • A history of sunburns or fragile skin. Skin that has been burned, sunburned, or injured from disease has a higher risk of skin cancer. Squamous cell and basal cell carcinoma occur more often in people who have more exposure to the sun or other sources of UV radiation over their lifetime.

  • Previous skin cancer. People who have had any form of skin cancer have a higher risk of developing another skin cancer. From 35% to 50% of people diagnosed with 1 basal cell carcinoma will develop a new skin cancer within 5 years. Therefore, people who have had 1 skin cancer need ongoing follow-up care to watch for additional cancers. See the Follow-up Care section for more information.

  • Inherited syndromes. Certain rare genetic conditions are associated with an increased risk of developing basal cell carcinoma. These conditions include nevoid basal cell carcinoma syndrome, which is also called Gorlin syndrome, and the very rare Rombo, Bazex-Dupré-Christol, and epidermolysis bullosa simplex syndromes, among others. Rare syndromes associated with an increased risk of squamous cell carcinoma include xeroderma pigmentosum, albinism, epidermolysis bullosa simplex, dyskeratosis congenita, and multiple self-healing squamous epitheliomata.

  • Weakened or suppressed immune system. People with a weakened immune system due to a stem cell or a solid organ transplant or diseases such as HIV/AIDS and certain types of leukemia have a higher risk of developing skin cancer, particularly squamous cell carcinoma. People taking immunosuppressive drugs have the same higher risk.

  • Arsenic exposure. Exposure to the poison arsenic may increase the risk of Merkel cell cancer.

  • Medications. In addition to medications that suppress the immune system, certain steroids and medications that make the skin very sensitive to sunburns, such as vandetanib (Caprelsa), vemurafenib (Zelboraf), and voriconazole (Vfend), have all been shown to increase a person’s risk of developing squamous cell carcinoma. So-called BRAF inhibitors, including dabrafenib (Tafinlar), encorafenib, and vemurafenib, have been shown to increase a person’s risk of developing squamous cell carcinoma by turning on a growth pathway in cells that tend to turn into this type of cancer (for example, cells with an HRAS mutation).

  • Previous treatment with radiation therapy. When a person receives radiation therapy as a cancer treatment, he or she has a higher risk of developing basal cell carcinoma. This risk increases over time, especially after 10 to 20 years. As a result, children who receive radiation therapy have a 6 times higher risk for developing a basal cell carcinoma.

  • Human papillomavirus (HPV). Research shows that this virus is a risk factor for squamous cell carcinoma, particularly if the person’s immune system becomes suppressed. Sexual activity with someone who has HPV is the most common way someone gets HPV. There are different types of HPV, called strains. Research links some HPV strains more strongly with certain types of cancers. There are vaccines available to protect you from some HPV strains.

Prevention

Different factors cause different types of cancer. Researchers continue to look into what factors cause non-melanoma skin cancers. Although there is no proven way to completely prevent these diseases, you may be able to lower your risk. Talk with your doctor for more information about your personal risk of cancer.

Reducing exposure to UV radiation, particularly by reducing time spent in the sun and avoiding indoor tanning devices, lowers the risk of developing skin cancer. This is important for people of all ages and is especially important for people who have other risk factors (see above).

Sun damage builds up over time, so it is important to take the following steps to reduce sun exposure and avoid sunburn:

  • Limit or avoid direct exposure to the sun between 10:00 AM and 4:00 PM.

  • Wear sun-protective clothing, including a wide-brimmed hat that shades the face, neck, and ears. Clothes made from fabric labeled with UV protection factor (UPF) may provide better protection. UV-protective sunglasses are also recommended.

  • Use a broad-spectrum sunscreen throughout the year that protects against both UVA and UVB radiation and is SPF 30 or more. Reapply at least 1 ounce of sunscreen to your entire body every 2 hours or every hour after heavy sweating or being in the water.

  • Avoid recreational sunbathing and do not use sun lamps, tanning beds, or tanning salons.

  • Examine the skin regularly. This should include examinations by a health care professional and self-examinations. Learn more about how to do a self-examination.

  • Taking nicotinamide, a form of vitamin B3, as a tablet twice daily showed a reduction in non-melanoma skin cancer by 23% in patients who had 2 or more previous skin cancers.

  • Talk with your doctor about this if you have higher risk for skin cancer.

Learn more about protecting your skin from the sun on Cancer.Net.

Limiting your sun exposure may reduce your body’s production of vitamin D, although some research suggests that most people may only need 15 minutes of sunlight exposure to produce enough vitamin D. People with limited sun exposure should talk with their doctor about how to include good sources of vitamin D in their diet, including the use of supplements. Your levels of vitamin D can be checked by your doctor using a simple blood test.

The next section in this guide is Screening. It describes the early warning signs of skin cancer and how to perform a self-examination. You may use the menu to choose a different section to read in this guide.