Diagnostic relevance of silver stained nucleolar organizer region (AgNORs) in benign and malignant breast lesions.

The present study is planned to assess the diagnostic relevance of silver stained nucleolar organizer regions (NORs) in discriminating benign from malignant lesions of the breast and to ascertain the interobserver variability in the enumeration of AgNOR counts. Forty four specimens of benign and malignant breast tissues were studied and mean number of silver stained nucleolar organizer regions (MNORA) have been counted in paraffin sections. Malignant lesions have a higher number of MNORA than benign lesions. These results also showed correlation between the AgNOR counts and size of the tumor, axillary lymph node status and age of the patient. Our results also indicate a close agreement between the two observers with limits of agreement. However, AgNOR counts are of little diagnostic importance since a broad zone of overlap exists between benign and malignant breast diseases despite significant higher mean counts in malignant lesions. AgNOR sequence could perhaps be of use to differentiate those two histological indistinguishable lesions. The tumor size and axillary lymph node involvement suggested to its prognostic significance also. Interobserver agreement further suggests the utility of AgNOR counts as diagnostic or prognostic discriminants in breast malignancies.