Squamous Cell Carcinoma

What is Squamous Cell Carcinoma?

Squamous cell carcinoma (SCC) is a type of skin cancer that originates in the squamous cells, which are flat cells found in the outer part of the epidermis (the skin's outermost layer). SCC is one of the most common types of skin cancer and is generally caused by prolonged exposure to ultraviolet (UV) radiation from the sun or tanning beds. It can also develop in areas of the skin that have been burned, exposed to chemicals, or chronically inflamed.

SCC often appears as a red, scaly, or crusty patch of skin, a sore that doesn't heal, or a growth with a raised, sometimes central depression. It can also present as a wart-like growth.

Locations: Commonly occurs on sun-exposed areas such as the face, ears, neck, lips, and backs of hands. However, it can develop anywhere on the body, including the genitals and inside the mouth.

Risk Factors

Several risk factors contribute to the development of SCC, including:

  • Environmental and Lifestyle Factors
    • Ultraviolet (UV) Radiation Exposure:
      • Prolonged exposure to sunlight, particularly UVB rays, is the most significant risk factor.
      • Tanning beds also increase the risk of SCC.
    • Chemical Exposure: Contact with certain chemicals, such as arsenic, tar, and some industrial chemicals, can increase the risk.
    • Smoking: Tobacco use, particularly smoking, is linked to an increased risk of SCC, especially in the mouth and throat.
    • Chronic Skin Inflammation or Injury: Long-standing wounds, burns, or scars can predispose to SCC.
  • Biological Factors
    • Age: The risk increases with age, with most cases occurring in individuals over 50 years old.
    • Gender: Males are more likely to develop SCC than females.
  • Skin Type: Individuals with fair skin, light hair, and light eyes and those who burn easily or have freckles are at higher risk.
  • History of Skin Cancer: Having a previous skin cancer, including basal cell carcinoma or melanoma, increases the risk of developing SCC.
  • Human Papillomavirus (HPV) Infection: Certain strains of HPV, particularly those affecting the genital area, can increase the risk of SCC.
  • Genetic Factors
    • Genetic Predisposition: Conditions like xeroderma pigmentosum, which affects DNA repair, significantly increase the risk of SCC.
    • Family History: A family history of skin cancer can be a contributing factor.
  • Immunosuppression
    • Organ Transplant Recipients: Those who have received organ transplants and are on immunosuppressive therapy are at higher risk.
    • HIV/AIDS: Immunosuppression due to HIV/AIDS increases the risk of SCC.
    • Medications: Long-term use of immunosuppressive drugs, such as those used for autoimmune diseases or after organ transplants, can increase the risk. 

Other Factors

  • Actinic Keratosis: These are precancerous skin lesions caused by sun damage and can develop into SCC if untreated.
  • Certain Medical Conditions: Conditions that cause chronic inflammation or immunosuppression can increase the risk.

Preventative Measures

Preventative measures for SCC primarily involve reducing exposure to risk factors and maintaining good skin health. Here are several key strategies:

  • Sun Protection
    • Use Sunscreen: Apply broad-spectrum sunscreen with an SPF of at least 30. Reapply every two hours, and after swimming or sweating.
    • Wear Protective Clothing: Long-sleeved shirts, wide-brimmed hats, and UV-blocking sunglasses can help protect your skin.
    • Seek Shade: Avoid direct sun exposure, especially between 10 a.m. and 4 p.m., when UV rays are the strongest.
    • Avoid Tanning Beds: Tanning beds increase the risk of all skin cancers, including SCC.
  • Regular Skin Checks
    • Self-Examinations: Regularly check your skin for any new growths, changes in existing moles, or other unusual skin changes.
    • Professional Skin Exams: Visit a dermatologist annually for a professional skin examination, or more frequently if you have a history of skin cancer or are at high risk.
  • Lifestyle Choices
    • Avoid Smoking: Smoking increases the risk of SCC, particularly on the lips.
    • Healthy Diet: A diet rich in fruits and vegetables can support overall skin health.
  • Protecting High-Risk Areas
    • Lips and Ears: These areas are particularly vulnerable. Use lip balm with SPF and ensure ears are covered or protected with sunscreen.
    • Post-Treatment Care: If you’ve had SCC before, follow up with your dermatologist regularly, as there is a higher risk of recurrence.
  • Avoiding Other Risk Factors
    • HPV Vaccination: Certain strains of the human papillomavirus (HPV) are associated with SCC, especially in genital areas. Vaccination can reduce this risk.
    • Managing Pre-existing Skin Conditions: Conditions like actinic keratosis (pre-cancerous lesions) should be treated promptly as they can develop into SCC.

By following these preventative measures, you can significantly reduce your risk of developing squamous cell carcinoma.