Squamous cell carcinoma
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.