The role of determining the nucleolar organizers in assessing the evolution of neoplasms

Abstract

Background Nucleolar organizer regions are parts of chromosomes that code ribosomal RNA and correlate to cellular proliferation. They have been identified by means of an argyrophilic technique that reveals NORs as black dots in the nuclei. The method has been recently applied in some malignancies, as lymphoma or melanoma. Only few investigations on hormonal-dependent tumours have been published. Our aim was to investigate on the total number of AgNORs and cell type of endometrial tumors. Material and Methods We studied 21 cases of formalin fixed paraffin embedded endometrial tumors including hyperplasia. The number of AgNORs was counted in both epithelial and stromal components. A total of 13 cases were benign and 8 malignant lesions. Results The total number of AgNORs was found to correlate with mitotic counts both in benign lesions and malignancies. The mean number of AgNORs increased from 2.79 in simple endometrial hyperplasia to 10.0 in adenocarcinoma. Conclusions Our data indicate that the AgNORs visualization can assist to differentiate between different malignancy grades of endometrial proliferations, especially between complex endometrial hyperplasia and atypical hyperplasia as well as endometrial adenocarcinomas.

Keywords

• Endometrial Hyperplasia
• Endometrial Adenocarcinoma
• AgNOR
• Mitotic count