Squamous Cell Carcinoma

Risk Factors

Squamous cell carcinoma, or SCC, is the second most common form of skin cancer in the United States. For this reason, it’s important to be aware of any risk factors that you may have for SCC. Risk factors are those things that may increase the chances of developing a condition. Knowing your risk factors is the first step in prevention and early detection.

There are two types of risk factors — those that can be controlled and those that cannot be controlled. In terms of controllable risk factors, the primary cause of most skin cancers is sun and ultraviolet radiation exposure and sunburn. These can be controlled by:

  • Reducing sun exposure
  • Wearing protective clothing
  • Avoiding sun exposure at midday, when ultraviolet light is most intense
  • Applying sunscreens regularly and frequently 
  • Using sunscreen year-round, even in winter
  • Avoiding sun lamps, tanning beds and tanning salons
  • Reducing or stopping tobacco use

Uncontrollable risk factors for skin cancer include:

  • Complexion: Skin cancer is more common in people with light-colored skin, hair and eyes.
  • Sun sensitivity: Those who are more likely to sunburn or get freckles, rather than tan, are considered sun sensitive.
  • Genetics: Having a family history of skin cancer increases the risk of developing the condition.
  • Age: Non-melanoma skin cancer is more common after age 40.
  • Weakened immune system: Conditions that weaken the immune system include long-term treatment with medications used to prevent organ rejection, lymphoma and human immunodeficiency virus, or HIV.
  • Ionizing radiation treatments: People who have had radiation exposure, such as radiation therapy or x-rays, are at higher risk of developing squamous cell carcinoma. This risk is directly related to the amount of radiation exposure, and the condition may appear 15 to 20 years after exposure.
  • Chemical exposures: Those who have a history of contact with arsenic, coal, industrial tar or paraffin are at higher risk for squamous cell carcinoma.
  • Xeroderma pigmentosum: This is a rare, inherited condition that reduces the skin’s ability to repair damage caused by sunlight.
  • Chronic skin ulcers.
  • Actinic keratosis: AK is a rough, scaly, slightly raised growth that ranges in color from brown to red and is about one millimeter to one inch in diameter. It’s found on sun-damaged areas of the body.

Skin cancer can develop in anyone, not just those with these risk factors. Healthy young people — even those with dark skin, hair and eyes — can develop skin cancer.