Early diagnosis and prevention of oral cancer and precancer: report of Symposium III.

Oral precancer encompasses several conditions and lesions. Among those entities included in the concept are leukoplakia, erythroplakia, lichen planus, and submucous fibrosis. For prevention, knowledge about etiologic and pathogenetic factors is imperative. It is well-known that excessive consumption of tobacco and alcohol has a bearing on the development of oral leukoplakia and probably also of erythroplakia. However, among leukoplakias, the idiopathic or cryptogenic type probably shows the most serious malignant potential. Involved in the development of such lesions may be general nutritional aspects, e.g., proper utilization of vitamin A. It is also well-known that iron deficiency has been linked to Plummer-Vinson's syndrome, showing a precancerous trait. Among factors involved in the pathogenesis of lichen planus is probably mental stress. Thus, stress factors and related neurological components have been linked to the immunological system. Lifestyle factors, such as nutrition, tobacco, and alcohol, and also mental environment may be of importance for the development of oral precancer and cancer.