Nontyrosine crystalloids in salivary gland lesions: report of seven cases with fine-needle aspiration cytology and follow-up surgical pathology.

We report a series of seven patients who underwent fine-needle aspiration (FNA) for clinically apparent parotid gland lesions. In all seven cases, numerous to abundant polyhedral, multifaceted (nontyrosine) crystalloids were noted in the background of scanty cellular specimens composed predominantly of oncocytic cells. Subsequent surgical excision showed that three of the seven glands revealed sialolithiasis and sialadenitis without evidence of neoplasia. The histology of the remaining four cases consisted of two Warthin's tumor, one oncocytic papillary cystadenoma, and one cellular benign mixed tumor. In all seven cases the nontyrosine crystalloids were found in highest concentrations in cystic spaces lined with oncocytic metaplastic cells. We conclude that nontyrosine cystalloids can be associated with both neoplastic and nonneoplastic salivary gland disease, and they may be a product of oncocytic cell secretion. Diagn. Cytopathol. 2000;22:167-171. Copyright 2000 Wiley-Liss, Inc.