Nucleolar organizer regions in human breast cancer.

The silver staining technique for demonstration of argyrophilic nucleolar organizer regions (AgNORs) was examined for their usefulness in routine clinical diagnosis for discrimination of benign breast diseases from malignant ones and for prognostic purposes. We examined the number of AgNORs in 56 cases of malignant breast lesion and 20 cases of benign breast disease, using routinely fixed material. We found a clear-cut difference between benign breast diseases as compared with breast carcinomas where the mean AgNOR count was significantly higher, whereas no statistically significant correlation was observed between AgNOR counts and survival rate of human breast cancer patients.