[Contribution to the pathogenesis of carcinoma after laryngeal epithelial dysplasia (author's transl)].

Between 1967 and 1980 laryngeal leukoplakia was clinically diagnosed in 86 patients. Histology revealed a true invasive carcinoma in 18 patients. Epithelial dysplasia grade I was found in 32 patients, grade II in 25 and grade III (carcinoma in situ) in 9 patients. 8 patients (14%) with dysplasia grade I and II subsequently developed carcinoma in situ or true invasive carcinoma. The average time lapse between first biopsy and histologically verified carcinogenesis was 5.1 years. No correlations was found to the histological grading.