A case of pleomorphic adenoma of the parotid gland metastasizing to a mediastinal lymph node

Benign metastasizing pleomorphic adenoma is a rare and controversial but distinct clinical entity. Although the definition of the term benign precludes metastatic disease, these tumors do not demonstrate any malignant features yet metastasize to distant sites. It remains to be determined whether these benign metastasizing pleomorphic adenomas are really low-grade salivary malignancies.