Diagnostic value of AgNOR method in thyroid cytopathology: Correlation with morphometric measurements

Abstract

A silver staining technique was applied to 51 thyroid smears. The numbers of silver‐stained nucleolar organizer regions (AgNORs) were counted, and the mean AgNOR and nuclear area per cell were determined with an image analyzer. The mean AgNOR count per cell was significantly higher in malignant than in benign lesions, but there was a considerable overlap. The mean AgNOR area and the mean SD of the AgNOR area per cell were significantly higher in carcinomas than in benign lesions (P = 10–9 and P = 5 × 10–10, respectively) and there were only two and one benign cases, respectively, of overlap. A strong correlation was observed between the mean AgNOR area and the mean nuclear area (r = 0.88), the former being a better discriminator between benign and malignant lesions. The AgNOR technique may contribute to routine thyroid cytopathology. Diagn Cytopathol 1996;14:140–144. © 1996 Wiley‐Liss, Inc.

Argyrophilic nucleolar organizer regions of thyroid lesions on fi ne needle aspiration smears

“…However there was overlap between some of the cases. Other studies done by Solymosi T et al 4 , Astora S 2 and Mehotra A 3 also showed higher mean AgNOR count in carcinomas than adenomas. Camergo RS did not find any difference in mean AgNOR count between adenoma and carcinoma.…”

“…3 It is well known that silver staining technique for nucleolar organizer regions (NORs) has been successfully applied to a wide variety of neoplastic lesions to distinguish benign from malignant lesions. 4 NORs are loops of DNA projecting into the nucleoli of the interphase nuclei and they are thought to encode for ribosomal RNA (rRNA). This rRNA is responsible for protein synthesis of the cell.…”

“…4 AgNOR is one of such marker which seems highly sensitive and specific to distinguish between benign and malignant thyroid lesions in smears because more accuracy is ensured after whole nuclei have been assessed. 2 In the current study mean AgNOR count was highest in papillary carcinoma (5.40 ± 0.86) and lowest in Hashimoto's thyroiditis (2.10 ± 0.3).…”

Evaluation of the Long-term Growth Potential of Benign Non-toxic Thyroid Nodules by the AgNOR Method; an 11-year Follow-up Study

“…The AgNOR method and morphometry were performed on the FNA samples as described earlier [9,10]. We calculated the following parameters: the mean AgNOR count per cell (AgNORc), the mean AgNOR area per cell (AgNORa) and the mean nuclear area.…”

“…Earlier, we found that the proliferative activity determined by argyrophilic staining of the nucleolar organizer region (AgNOR) of thyroid cells displays significant differences between benign and malignant thyroid lesions [9] in FNA samples. In our present work, we tested if that parameter can predict the growth potential of benign thyroid nodules.…”