AgNOR count as objective marker for dysplastic features in oral leukoplakia.

Abstract

Dysplasia is an important feature of leukoplakia. Because agreement among oral pathologists is poor regarding lesional diagnosis, silver stainable nucleolar organizer regions (AgNORs) as replicatory markers may have a place in objectively characterizing dysplasia in tissue specimens. We studied 41 normal oral epithelia, 51 oral leukoplakia (26 dysplastic, 25 non-dysplastic), and 51 cases of squamous cell carcinoma specimens for their mean AgNOR counts. Mean AgNOR counts increased gradually from normal epithelium to non-dysplastic to dysplastic leukoplakia to squamous cell carcinoma. Using ROC analysis, we determined a mean AgNOR count cut-point (2.37) that can be used to distinguish between dysplastic and non-dysplastic leukoplakia. The test had a sensitivity of 75% and specificity of 83% with area under the curve being 88%. Mean AgNOR count could be a valuable criterion for defining objective parameters for diagnosis/determination of dysplasia distinguishing between dysplastic and non-dysplastic leukoplakia.