[Potentially malignant disorders of the oral mucosa]

Potentially malignant disorders of the oral mucosa. The term "precancerous" is now abandoned in favor to « potentially malignant disorder » which provide a better view of the evolution a far from systematic. Of these disorders, leukoplakia is the most common while erythroplakia is rare. Their diagnoses are still defined by exclusion of other known white or red lesions. Despite progress in molecular biology, there is no marker enabling to predict malignant transformation. When feasible, excision of these lesions is recommended, irrespective of the presence or the absence of dysplasia, a pure histologic notion. It is unknown if such removal can really prevent the development of a squamous cell carcinoma. The risk of malignant transformation of oral lichen planus, lower than in leukoplakia, is better known. There is no therapeutic enabling to prevent such event. Other potentially malignant disorders such as oral submucous fibrosis, actinic cheilitis, lupus and immunodeficiency conditions are rare.