Ag-NOR technique in fine needle aspiration cytology of salivary gland masses.

Because of their complexity, salivary gland lesions are often difficult to identify correctly with fine needle aspiration cytology. To see whether the Ag-NOR staining technique for nucleolar organizer regions would be useful in this respect, we studied a series of smears from benign and malignant salivary gland lesions. The smears, previously treated with Papanicolaou and May-Grünwald-Giemsa stain, were destained and restained with Ag-NOR silver. The correlation between the cytologic-histologic diagnosis and the number of Ag-NORs in benign (sialadenitis, pleomorphic adenoma, oncocytoma and Warthin's tumor) and malignant lesions (adenoid cystic carcinoma, adenocarcinoma, carcinoma ex pleomorphic adenoma and squamous carcinoma) was statistically significant (P = less than .05). The Ag-NOR technique appears useful in the diagnosis of salivary gland lesions. One great advantage is that previously stained slides can be reused for silver staining, thus providing an excellent guide to the diagnosis, especially in doubtful cases and when corresponding histologic specimens or extra unstained slides are unavailable.