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Given the history of chronic smoking, it would be essential to include smoker's keratosis on the differential diagnosis. It is, however, important to note that this patient stopped smoking eleven years ago and the white lesion did not appear until recently. Smoker's keratosis can still be included on the differential diagnosis, but it would be unlikely. The histology in this case is not supportive of smoker's keratosis.
Smoker's keratosis should be among the many oral changes associated with the use of tobacco (6), specifically smoked tobacco. In a study in Pakistan which examined the normal gingiva of 16 patients, smokers were found to have more epithelial keratosis in general than non-smokers (7). Smoker's keratosis is most common in middle-aged males and appears as a white lesion, ranging in texture from smooth to rough to verruciform, usually occurring in the buccal mucosa, mucobuccal fold and/or floor of mouth. Histologically, the lesions range from benign hyerkeratosis and acanthosis to various grades of epithelial dysplasia, and to invasive squamous cell carcinoma. Treatment depends on the histology and the clinical presentation. It may range from cessation of tobacco use (which may lead to the reversal of the white lesions) to surgical or laser excision.