Immunohistochemical expression of metallothionein in pleomorphic adenoma of minor salivary glands: a role in the control of apoptosis?

Pleomorphic adenoma is the most common benign neoplasm of both the major and minor salivary glands. The histological features are diverse and are characterized by the involvement of epithelial-myoepithelial structures. Metallothionein is a cysteine-rich protein present in myoepithelial cells of several benign and malignant neoplasms.