Malignant Minor Salivary Gland Tumors

Epidemiology

The same malignancies that arise in the parotid gland can arise in the submandibular gland. An interesting paradox is that the smaller the salivary gland, the greater the likelihood that a tumor originating from the submandibular gland will be malignant. Thus the incidence of a salivary gland tumor being malignant in the submandibular gland is higher than in the parotid gland.

Clinical Findings

Patients often present with asymptomatic masses that have been present for several months. Advanced lesions may result in facial numbness or facial nerve palsy.

Pathology

The malignancies that constitute malignant salivary gland tumors include adenoid cystic carcinoma, mucoepidermoid carcinoma, and adenocarcinoma. Many investigators now include low grade polymorphous adenocarcinoma as a tumor of minor salivary gland origin. The most common malignancy of the minor salivary glands is adenoid cystic carcinoma.