Abstract
Three parameters of epithelial dysplasia of the larynx, namely, the expression of oncogene product (ras p21, EGF-R), nuclear DNA contents measured by flowcytometry and the proliferating activity (Ki-67, PCNA), were examined to determine the appropriate clinical treatment and the prognosis. Dysplasia was classified into low grade and high grade depending upon the degrees of cellular atypia and polarity-disorder in the depths of the epithelium. Fourteen of 20 cases with high grade dysplasia and 7 of 21 cases with low grade dysplasia were positive to ras p21. Two of 6 cases with high grade dysplasia and 1 of 5 cases with low grade dysplasia were positive to EGF-R. Four of 8 cases with high grade dysplasia and 2 of 7 cases with low grade dysplasia had a DNA aneuploid pattern as determined by flow cytometric DNA analysis. High grade dysplasia had higher Ki-67 and PCNA labeling indeces than low grade dysplasia. These three parameters may be useful in deciding the therapeutic modalities and the prognosis of dysplasia.