EFFECTIVENESS OF AgNOR STAINING IN DISTINCTION OF ENDOMETRIAL ADENOCARCINOMA, HYPERPLASIA AND NORMAL ENDOMETRIUM

Nucleoalr organizer Region (NORs) are loops of DNA that transcribe to ribosomal RNA. A silver colloid staining techique to identify nucleolar organizer region associated protein (AgNOR’s) can visualize them by intranuclear black dots. The objective of the present research is to determine to what extent the staining method can be effective in screening and diagnosis of endometrial lesions. In this investigation, the technique is applied to 120 sections of endometrial tissue. The specimens were taken from patients admitted to Shahid Akbar-Abadi Hospital in Tehran between 1372 - 1376. These sections were obtained either after curettage or from hysterectomy specimens. The histological diagnosis are as follows: normal proliferative (n=30) or secretory (n=30) endometrium, simple cystic hyperplasia (n=29), complex hyperplasia (n=6) and adenocarcinoma (n=25). The average number of NOR(s) in normal proliferative, normal secretory, simple and complex hyperplasia and adenocarcinomatous tissues were 8.9, 5.7, 9.7, 10.3 and 14.6 respectively. There are clearly significant variations between these average counts, as quantified by an ANOVA (p<1.42E-43). Power analysis of the results shows that about 83% of variance of the dependent variable (NOR count) is due to the effects of independent variables, that is the aforementioned lesions. The sharp variation between NOR counts in different normal tissues with each other and with abnormal pre malignant and malignant lesions, and also between pre malignant and malignant lesions, strongly suggest using AgNOR in differential diagnosis of endometrial lesions.