An adenoid cystic carcinoma arising from the salivary gland. It is characterized by the presence of epithelial and myoepithelial cells forming tubular, cribriform, and solid patterns. It usually presents as a slow growing mass. Patients may experience pain because of the tumor propensity for perineural invasion. The tumor may follow an aggressive clinical course with recurrences and mestastases to distant sites including lungs, bones, brain, and liver. [from
NCI]