Chronic hyperplastic laryngopathies are considered precancerous lesions because of their possible transformation in time into malignant epithelial neoplasia. We studied 130 patients affected by "hyperplastic laryngeal lesions" according to their semeiological characteristics. The lesions affected the vocal cords in 127 cases and in only 3 cases the ventricular bands. All patients underwent microlaryngoscopy while under general anesthesia and were treated by limited excision (37%) or total stripping (63%). The histomorphological classification by Kleinsasser (7) was used. The following clinical checks showed that 30 out of 48 patients (62.5%) treated by partial stripping recovered; in 11 the lesion relapsed (23%) and in 7 cases (14.5%) a carcinoma appeared. Of those cases treated by total stripping 65 patients (79%) recovered, 12 (15%) relapsed and 5 (6%) showed carcinoma. In conclusion we noticed the appearance of a malignant lesion after surgery in 12 out of 130 cases (9.2%). The cancerization was about 3 times more frequent in patients with histological results of degree II than in those with degree I (17% vs. 6%). Our study confirms that the laryngeal hyperplastic lesion represents a possible passage to cancer in a limited number of cases (< 10%), but with a triple probability for degree II dysplasia in respect to degree I. The patients affected by dyskeratosis, regardless of type of lesion, need a regular follow-up and immediate radical surgery because of the frequent incidence of relapse.