Fine-needle aspiration cytology of salivary gland: a review of 341 cases

Three hundred and forty-one salivary gland fine-needle aspiration (FNA) cytology specimens taken over a 6-yr period were reviewed and correlated with clinical and/or histological findings. The aspirates were derived from parotid gland (212 cases), submandibular gland (124 cases), and minor salivary gland (5 cases). The major diagnostic categories were unsatisfactory (10 cases), normal (100 cases), sialadenitis (74 cases), cyst (34 cases), lipoma (5 cases), pleomorphic adenoma (55 cases), Warthin's tumor (36 cases), and malignancy (27 cases). The latter included 14 primary salivary neoplasms (4 lymphomas of mucosa-associated lymphoid tissue (MALT) type, 3 adenocarcinomas, 2 squamous carcinomas, 2 adenoid cystic cacinomas, and one case each of carcinoma ex pleomorphic adenoma, undifferentiated carcinoma, and high-grade mucoepidermoid carcinoma), and 13 metastases, 9 of which were derived from squamous carcinomas of head and neck origin. Clinicopathological review showed that 88 of 91 (97%) benign epithelial tumors and 27 of 31 (87%) malignant neoplasms with adequate FNA sampling were accurately diagnosed cytologically. False-negative results were caused by sampling error (7 cases), most notably in cystic tumors, or were due to misinterpretation of uncommon neoplasms (3 cases). The overall sensitivity, specificity, and accuracy were 92%, 100%, and 98%, respectively. FNA cytology provides accurate diagnosis of most salivary gland lesions and contributes to conservative management in many patients with nonneoplastic conditions.