Epithelial-myoepithelial carcinoma of the salivary gland.

Epithelial-myoepithelial carcinoma of salivary gland is a rare tumor only recently described in the English language literature. This paper adds four new cases to the 30 which have previously been reported. The clinical presentation of this unusual neoplasm is documented in the accompanying case reports and the appropriate surgical management outlined. Follow-up ranges from six months to 12 years. The histopathological characteristics of this interesting tumor, in particular its classical biphasic cellular appearance, are described in detail both by light and electron microscopy. On the basis of histologic appearance and biological behavior, the authors postulate that epithelial-myoepithelial carcinoma is an uncommon variant of adenoid cystic carcinoma.