Atypical cilia in hyperplastic, metaplastic, and dysplastic human bronchial mucosa.

Twenty-two cases displaying potentially precancerous epithelial changes of the bronchial mucosa--including basal and goblet cell hyperplasia, epidermoid metaplasia, and dysplasia--showed a wide variety of cilial abnormalities on the ultrastructural level. The changes comprised abnormal configurations of the ciliary plasma membrane, variations in the amount of ciliary matrix, disorganization of basal bodies, and diverse alterations of the axonemal microtubular pattern. More than one such alteration was observed in one and the same case, and there was no correlation with the actual type of epithelial lesion nor the degree of dysplasia. These changes, interpreted as abnormal ciliary regeneration in severely damaged ciliated cells, are potentially reversible and seem to represent a nonspecific response of the affected cells to an ample spectrum of noxes. Their diagnostic significance is poor, especially with regard to the modification of the axonemal microtubular pattern, unless the entire clinical picture suggests an immotile cilia syndrome.