AgNOR counts as a discriminator of lesions of the endocervix.

Recently the argyrophil for staining proteins associated with nucleolar organizing regions (AgNORs) has been applied widely in cytohistopathology in various malignancies. Nucleolar organizer region-associated proteins (NORs) are located on the short arm of chromosomes 13, 14, 15, 21 and 22. We applied the technique to 78 cytologic smears from the endocervix stained with the Papanicolaou technique. These included 36 normal endocervical cases, 17 reactive endocervical cases, 19 dysplastic endocervical cases and 6 endocervical adenocarcinoma cases. Statistically significant differences were found between AgNOR counts from normal endocervical smears and smears of endocervical gland dysplasia (P < .001), between normal endocervical smears and smears of endocervical adenocarcinoma (P < .001), between reactive endocervical smears and smears of endocervical gland dysplasia (P < .001) and between reactive endocervical smears and endocervical adenocarcinoma (P < .005). The AgNOR technique appears useful as an adjunct in the diagnosis of endocervical lesions.