The role of viruses in squamous cell carcinoma of the oropharyngeal mucosa.

The development of squamous cell carcinomas of the oropharyngeal mucosa may involve many factors, including viruses. This review examines the evidence that viruses could be involved in the etiology of oral cancer, and shows that the evidence for a role of different viruses varies from very weak to very persuasive. Papillomaviruses are probably involved in the etiology of some carcinomas, particularly those of the oropharynx, and some herpes viruses may be involved as well. On the other hand some viruses can cause cancer in experimental situations but not in humans. Thus the importance of viruses in oral cancer is not always clear and must be evaluated with care. Those viruses that are associated with the disease provide targets for therapy and for diagnostic assays.