A study of the utility of silver nucleolar organizer regions in categorization and prognosis of salivary gland tumors.

Background: this study aimed at assessing the utility of silver nucleolar organizer region (AgNOR) staining in categorization and prognostication of salivary gland tumors.
Methods: Twenty-seven malignant salivary gland tumors, 16 benign neoplasms, and 6 chronic sialadenitis lesions were stained using the technique described by Ploton et al. (1986).
Results: The mean AgNOR counts for inflammatory lesions (1.67 +/- 0.19) and benign neoplasms (1.67 +/- 0.11), were less than for malignant neoplasms (3.59 +/- 0.55), P < .05. There was no significant difference between the mean AgNOR counts of different specific histological types and grades of malignant neoplasms. In addition, no correlation was found between mean AgNOR counts and the clinical course of malignant or benign salivary gland neoplasms.
Conclusion: Our results suggest that AgNOR staining is useful for distinguishing benign from malignant lesions, but is neither helpful for discriminating between histological types and grades of malignant neoplasms, nor prognostication of malignant salivary gland neoplasms.