[Quantitative study on nucleolar organizer regions in salivary gland tumours]

The argyrophil staining technique for nucleolar organizer regions (NOR) had been applied to a series of benign and malignant salivary gland tumours. We have studied 38 salivary gland tumours, 16 benign and 22 malignant. In all specimens clearly defined silver-stained intranuclear AgNOR dots were visible. The differences between the numbers of AgNORs in the benign and malignant groups, notably pleomorphic adenomas, adenoid cystic carcinoma, mucoepidermoid carcinoma and adenocarcinoma, were highly significant. This result suggested that the AgNOR technique is of diagnostic help in distinguishing between these salivary gland tumours.