II. Squamous Cell Carcinoma Causes:
Repeated, prolonged sun exposure causes skin damage which may develop into squamous cell carcinoma.
The sun damage responsible for a squamous cell carcinoma usually occurred years before the cancer begins.
Squamous cell carcinomas are most common on the face because the face receives more sunlight than other parts of the body.
Fair-skinned individuals are more prone to skin cancer than darker persons, since skin pigment protects the skin. Persons of African ancestry with very dark skin practically never get squamous cell carcinoma of the skin.
People who get one squamous cell carcinoma are likely to develop more. Often people will develop a second squamous cell carcinoma close to the spot were one has been treated because the surrounding skin is just as damaged by the sun as the skin where the first squamous cell carcinoma grew.