SIGNIFICANCE OF AGNOR COUNTS FOR DISTINGUISHING CARCINOMA FROM ADENOMA AND HYPERPLASIA IN PARATHYROID-GLAND

Nucleolar organizer region proteins, which can be stained and visualiz ed by an argyrophil technique (AgNORs), are markers of cell activities , such as DNA transcription and proliferation, and they are useful for differential diagnosis between benign and malignant tumors. We counte d both AgNOR numbers in 25 parathyroid lesions (three carcinomas, 11 a denomas, 10 hyperplasias, and one hyperplasia with carcinoma) to deter mine if the AgNOR number could be useful as a diagnostic aid in parath yroid neoplasms and hyperplasias, because it is often difficult to his topathologically distinguish among these lesions. The AgNOR numbers we re significantly higher in carcinomas (3.18 +/- 0.05) than in adenomas (1.67 +/- 0.30, P <.001) or hyperplasias (1.85 +/- 0.16, P <.001), bu t there was no significant difference between adenomas and hyperplasia s. These results suggest that AgNORs may be useful as an adjunct to di scriminating carcinomas from adenomas or hyperplasias in the parathyro id gland. Copyright (C) 1997 by W.B. Saunders Company.