Adenoid cystic carcinoma of the mandible.

Primary adenoid cystic carcinoma of the jaws is a rare neoplasm of salivary gland origin with only nine cases having been previously reported. It is characterized by a slow clinical course and insidious growth pattern that frequently results in metastasis or recurrence, or both. The example presented here was associated with retained root fragments in the mandibular molar region and had a classic histologic pattern.