Application of AgNOR (Argyrophilic Nucleolar Organizer Regions) Staining in Distinction of Non Neoplastic and Neoplastic Endometrial Lesions

Study of AgNOR has been identified as a reliable indicator of cell proliferation and in turn, allows a clear distinction between benign, premalignant, and malignant epithelial changes. The aim of this study was to analyze and evaluate the application of AgNOR method as diagnostic tool in non-neoplastic and neoplastic lesions of endometrium. The study included evaluation of AgNOR staining on a total of 50 cases of endometrial specimens obtained by hysterectomy and dilatation and curettage sent for histopathology. Paraffin blocks of the above selected cases were taken for hematoxylin and eosin, and AgNOR staining. Out of total cases of endometrial specimens studied, sixteen cases were normal proliferative and secretory endometrium served as control. Twenty nine cases were non-neoplastic lesions and five cases were neoplastic. In present study, 8 cases of proliferative phase endometrium showed mean AgNOR count being 2.35 and 8 cases of secretory endometrium showed mean AgNOR count being 1.55 AgNOR/nucleus. In non-neoplastic lesion group, simple hyperplasia, complex hyperplasia and complex hyperplasia with atypia showed mean AgNOR count being 3.41, 3.71 and 4.3 AgNOR/nucleus respectively. In neoplastic lesions benign endometrial polyp showed mean AgNOR count 3.48 AgNOR/ nucleus, whereas cases of endometrial carcinoma showed mean AgNOR count 5.62 AgNOR/nucleus. ANOVA t test was done and all the values were found to be statistically significant (p value< 0.0001). Present study suggests that AgNOR counts are reliable markers of endometrial proliferation and allow a clear distinction between non-neoplastic and neoplastic lesions of endometrium.