Evaluation of AgNORs on FNA smears and tissue sections in benign and malignant breast diseases

AgNOR scoring on breast tissue has shown a significantly higher count in malignant breast lesions in comparison to benign lesions and AgNOR staining on breast aspiration smears has been found superior to staining of histological sections. The present study aims at a comparative evaluation of mean AgNOR (mAgNOR) counts on the cytologic smears and the corresponding histologic sections in the various benign and malignant lesions of the breast.

A one step silver colloidal staining procedure was employed for demonstration of AgNORs on aspiration smears and the corresponding histologic sections in fifty patients with breast lumps, 38 of these had a benign breast disease while 12 harboured a malignant lesion. AgNOR counts were expressed as mean AgNORs per nucleus (mAgNOR score).

The AgNORs in benign lesions were fewer, small, uniform, and mostly centrally placed where as those in malignant lesions were irregular, generally large and scattered. The mean mAgNOR count in benign breast lesions was 3.3; S.D 1.49 on FNA smears and 2.3; S.D 1.22 on histologic sections (p<0.001). In malignant diseases of the breast the mean mAgNOR score was 6.53; S.D 2.73 on FNA smears and 4.98; S.D 1.53 on histologic sections (p>0.1). The mAgNOR scores for the malignant breast lesions were significantly higher than those for benign lesions on both cytologic smears and histologic sections (p<0.001).

Though a broad overlap between benign and malignant lesions limits its use as a sole diagnostic criterion, however, AgNOR scoring can prove to be a simple and yet a very useful tool in predicting tumour progression and patient survival.