Interphase nucleolar organizer region distribution in the tissues of oral leukoplakia, oral submucous fibrosis and oral cancer.

The AgNOR technique, was applied to oral tissue sections of 185 oral cancer, 42 oral leukoplakia, 37 oral submucous fibrosis and 10 normal subjects to investigate whether any correlation held good in these different tissues. Compared to the AgNOR counts in normal oral epithelium, there was a gradation in increase in the mean AgNOR counts from oral leukoplakia to oral submucous fibrosis to oral carcinoma (P<0.01). This suggests that AgNOR count parallels with the degree of neoplastic transformation of oral epithelium. Three oral submucous fibrosis patients who showed very high AgNOR counts as that of oral cancer patients, later developed oral carcinoma. Among the oral cancer tissues, the moderately and poorly differentiated subtypes showed higher AgNOR counts and scattered distribution pattern than the well differentiated subtype which showed a clustered distribution pattern. These results suggest that AgNOR technique can be utilised as a diagnostic and prognostic indicator in premalignant and malignant oral tissues.