The authors value the distribution of some parameters such as age, sex, life habits, kind of clinical diagnosis and its relation to histological diagnosis in a population of 110 patients heterogeneous for rank and provenance. After describing the kind of casualty department aid, they explain the meaning of the word leukoplakia and underline the difficulties of clinical diagnosis: the macroscopic appearance of the white patch (according to WHO definition) is often comparable to other oral diseases either classified as precancerous lesions or not.