Salivary gland tumors of the mandible

Primary central salivary gland carcinomas of the mandible are uncommon neoplasms. Consequently, their proper diagnosis is often in doubt. We retrospectively studied the cases of 16 patients treated at The University of Texas M. D. Anderson Cancer Center and the Institut Gustave Roussy from 1950 to 1990. Patients ranged in age from 24 to 76 years (mean, 51 years). Nine patients were women and seven were men. Each case involved either the angle or the posterior body of the mandible. Swelling, pain, and trismus were the most frequent complaints. For all patients, radiography revealed a cystic defect resembling an osteolytic odontogenic lesion or metastasis. Five histologic types of carcinoma were diagnosed: seven cases of mucoepidermoid carcinoma (five low-grade and two high-grade), four cases of adenoid cystic carcinoma, two cases of adenocarcinoma, two cases of acinic-cell carcinoma, and one case of epithelial-myoepithelial carcinoma. All patients were treated with wide surgical excision. Eight patients received postoperative irradiation. Five patients with low-grade mucoepidermoid carcinoma, two with acinic-cell carcinoma, and one with epithelial-myoepithelial carcinoma were free of disease 2 to 15 years after initial treatment (mean, 6.2 years). Two patients with adenoid cystic carcinoma are living with lung metastasis. The remaining six patients died of their carcinomas within 4 years after initial treatment. Because of their unique morphology and clinical behavior, these tumors should be distinguished from other intraosseous neoplasms of the mandible, including those with clear-cell patterns.