Content and distribution of glycogen in oral epithelial dysplasia.

Forty-four oral lesions with epithelial dysplasia and 25 other benign and malignant lesions of the oral mucosa were examined after staining with hematoxylin-eosin and diastase controlled PAS. The intensity of the PAS-positivity for glycogen, the grade of dysplasia, the type of keratinization and the degree of subepithelial inflammation were recorded. Histologically normal epithelium at the margins of the lesions were used as controls. The presence and amount of glycogen in normal epithelium at the margins of the lesions were used as controls. The presence and amount of glycogen in normal epithelium at the margin of the lesions were used as controls. The presence and amount of glycogen in normal epithelium varied with the form of keratinization in that non- or parakeratinized epithelium was rich in glycogen whereas there was a negative glycogen-reaction in orthokeratinized epithelium. The most striking feature was an abrupt limitation of the glycogen at the junction between nondysplastic and dysplastic epithelium. The difference in the amount of glycogen in normal and dysplastic epithelium as assessed semiquantitatively, was statistically significant. There was no statistically significant difference in glycogen content with different degrees of dysplasia. The diastase controlled PAS-staining may therefore be a useful method of distinguishing dysplastic from nondysplastic epithelium in doubtful cases. Pseudoepitheliomatous hyperplastic epithelium covering granular cell myoblastoma did not contain any glycogen. Five of six squamous cell carcinomas and four verrucous carcinomas contained no demonstrable glycogen. Glycogen was present in the epithelium of the cases of lichen planus and "denture hyperplasia" investigated.