[Tumors of different histological type in unilateral salivary glands: a case report].

Tumors of synchronous benign and malignant in unilateral salivary glands have rarely been reported. A case of 21-year-old girl who was diagnosed as synchronously adenoid cystic carcinoma of the left parotid and pleomorphic adenoma of the left submandibular gland. The classification, clinic pathology, diagnosis, possible mechanism were discussed based on similar literatures.