Squamous Cell Carcinoma
carcinoma is a cancer that develops mostly in the thin, flat cells anatomically known as squamous epithelial
cells, which are found in grand quantity in the epidermis of the skin. Although the tumor is commonly found on
the skin, it is sometimes developed in the lining of the digestive tract, lungs, as well as other tissues of the
body such as the lips, mouth, esophagus, urinary bladder, prostate, lung, vagina, and cervix.
Squamous cell carcinoma of the skin, which develops mainly from superficial layers
of the epidermis where cells seem joined together like thorns to ensure cohesion and strength of the skin
surface, tends to grow on lesions that previously existed. It is therefore important to seek medical care if you
have any form of pre-cancerous skin lesion (Actinic keratosis for instance) on your skin.
Cutaneous squamous cell carcinoma is the second most common cancer of the skin in
order of frequency, after basal cell carcinoma. In the United States, it is estimated that 700,000 new cases of
the disease are diagnosed annually. Diagnosis is twice as common in men than in women, and the disease rarely
occurs before age 50, mostly from 70 years.
This type of skin cancer can affect any part of the body, including the oral and
genital mucosa, but it is most common on areas of skin exposed to the sun such as the face, ears, lower lip,
bald scalp, neck, backs of hands, arms and legs. Often these areas of skin show signs of sun damage, such as the
presence of wrinkles, brown spots or loss of elasticity.
People with fair skin, light hair and blue, green or gray eyes, have a higher risk
of developing squamous cell carcinoma. But anyone who is constantly exposed to sunlight has also consistently
increased the risk of being diagnosed with the tumor. People whose job requires long hours of work outside and
those who engage in outdoor recreation are particularly vulnerable. Individuals with known basal cell carcinoma
as well as people with specific genetic diseases, such as xeroderma pigmentosum (an autosomal recessive disorder
characterized by extreme sensitivity to ultraviolet rays from sunlight), are also more likely to have squamous
The majority of skin cancers in people with dark skin are squamous cell carcinomas,
which usually occur on areas of skin where there previously existed a burn or an inflammatory disease of the
skin. Although individuals with dark skin are less likely than fair-skinned people to have a skin cancer, it is
still essential that they protect themselves from the sun.
Ferrucci LM, Cartmel B, Molinaro AM et al. “Indoor tanning and risk of
early-onset basal cell carcinoma.” J Am Acad Dermatol 10.1016/j.jaad.2011.11.940. (Article in
Squamous Cell Carcinoma - Causes and Risk Factors". Retrieved September 2,
Grossman D, Leffell DJ. “Squamous cell carcinoma.” In: Wolff K et al.
Fitzpatrick’s Dermatology in General Medicine, 7th edition. USA. McGraw Hill Medical; 2008, p.
Squamous Cell Carcinoma Types