The estimation of proliferative activity by pcna and AgNORs in leukoplakia and squamous-cell carcinoma of the oral cavity.

The proliferating activity of leukoplakia and squamous cell carcinoma (SCC) was estimated using proliferating cell nuclear antigen (PCNA) immunostaining and silver-binding argyrophilic nucleolar organizer region (AgNOR) staining. Twenty-eight leukoplakias and 15 SCCs of the oral cavity were used in this study. The mean+/-S.D. of PCNA LI and AgNOR counts were 7.7+/-6.0% and 2.43+/-0.68/nucleus in leukoplakias, and 22.3+/-11.6% and 4.77+/-1.49/nucleus in SCCs. Both of PCNA LI and AgNOR counts were significantly higher in SCCs than in leukoplakias. There was a significant linear correlation between PCNA LI and AgNOR counts (p=0.0022) in leukoplakias, but not in SCCs. In the series of leukoplakias, PCNA LI apparently increased in leukoplakias with dysplasia and malignant transformed cases. Our data suggest that PCNA LI and AgNOR counts are useful markers of proliferating activity, and PCNA LI might be a prognostic factor of leukoplakias.