Rodu and Cole conducted a review of 21 studies on smokeless tobacco to determine the risk of cancer of the oral cavity and upper respiratory tract associated with different types of smokeless tobacco. Participants in the studies had used chewing tobacco, dry snuff, and/or moist snuff. The review indicated that the use of chewing tobacco or moist snuff was not associated with a significant increase in oropharyngeal cancer risk, but the use of dry snuff was associated with a 4-fold increase in risk for cancer of the oropharyngeal cavity and the larynx. Commentary by other reviewers cautioned that the majority of the studies reviewed in this study did not control for cigarette smoking and alcohol use, 2 important co-founders associated with oral cancer. More information on the scientific quality of the reviewed studies would have been helpful in terms of evaluating the reliability of the primary conclusions, according to these reviewers.
(Source: Journal of Evidence-Based Dental Practice, Vol. 3, No. 4, 2003)