Squamous cell carcinoma

Nature

Squamous-cell carcinoma (SCC), also known as epidermoid carcinoma, comprises a number of different types of cancer that begin in squamous cells. These cells form on the surface of the skin, on the lining of hollow organs in the body, and on the lining of the respiratory and digestive tracts.

Despite sharing the name "squamous-cell carcinoma", the SCCs of different body sites can show differences in their presented symptoms, natural history, prognosis, and response to treatment.

Source: Wikipedia

Incidence 
The risk of squamous cell carcinoma increases by 50% with smoking. In a 1996 US study of 107,000 nurses, squamous cell carcinoma occurred 50 percent more frequently in smokers than in those who had never smoked. Smoking interferes with the skin's ability to protect itself against damage by free radicals, highly reactive substances that are omnipresent in tobacco smoke.
Narrower 
Type 
(G) Very specific problems