Salivary Gland Tumors: A Clinicopathologic Analysis From Taipei Veterans General Hospital

BACKGROUND: The aim of this study was to investigate the epidemiological and clinical characteristics of salivary gland tumors (SGTs) in a Taiwanese population and to provide data for comparison with other studies in various locations and racial populations. METHODS: We retrospectively analyzed the medical records of 559 patients with tumors of the salivary glands who were surgically treated from 2002 to 2017 at a single institution. RESULTS: There were 430 benign and 129 malignant tumors with a mean age of 53.5 years (range, 1-91 years). The mean age of patients with benign SGTs was 52.6 years, and the mean age of patients with malignant SGTs was 55.8 years. Most findings were similar to those reported in literature, with some variations. The salivary tumors slightly predominated in males. There were no differences in age and incidence of benign or malignant major SGTs between males and females. The frequency was 76.9% for benign tumors (430 patients) and 23.1% for malignant tumors (129 patients). The majority of the tumors occurred in the parotid gland (351 cases), followed by the submandibular gland (152 cases), the minor salivary glands (46 cases), and, lastly, the sublingual gland (10 cases). Minor SGTs occurred most frequently on the palate, with pleomorphic adenoma, the most frequent benign tumor type, and adenoid cystic carcinoma and mucoepidermoid carcinoma, the commonest malignant tumor types. Tumors of the sublingual gland were rare, but 80% were malignant. CONCLUSIONS: In our series, SGTs were uncommon neoplasms that typically arose in the parotid gland. Benign tumors were far more common than malignant tumors. Pleomorphic adenoma was the most common benign tumors. Adenoid cystic carcinoma and mucoepidermoid carcinoma constituted the most common malignancies. Almost 60% of the tumors arising from minor salivary glands were malignant; thus, special care must be taken when these glands are affected.