Epithelial-myoepithelial carcinoma of the parotid gland: Clinicopathological aspect, diagnosis and surgical consideration

Abstract

The present paper describes the clinical and pathological features of epithelial-myoepithelial carcinoma (EMC) of the parotid gland. This rare tumor represents <1% of all salivary gland tumors and arises most commonly in the parotid gland, but it has also been described in the submandibular gland, minor salivary glands and palate. EMC is considered to be a low-grade malignant tumor that may commonly recur locally after resection in 23-50% of cases. The complex and varied morphological expression of this neoplasm has attracted numerous investigators, who have presented valuable but often contradictory data. After an in-depth analysis of the clinicopathological aspects of EMC, we speculate that adequate resection with negative soft-tissue margins is the minimum recommended and necessary therapy.

A Rare Case of Clear Cell Carcinoma of the Parotid Gland in Iran

“…An epithelial-myoepithelial carcinoma is a low-grade malignant neoplasm of the salivary gland, and in rare cases, of the lacrimal gland (4,6,8). It is identified by its biphasic morphology, with a cuboid luminal population of cells and eosinphilic cytoplasm (4,7).…”

“…It is identified by its biphasic morphology, with a cuboid luminal population of cells and eosinphilic cytoplasm (4,7). These cells are similar to intercalated duct cells and surrounded by large polygonal myoepithelial cells containing clear cytoplasm (4,7). Epithelial-myoepithelial carcinomas mostly occur in adults in their 60s and 70s, with a female to male ratio of 2:1 (5, 6).…”

“…The large lobular growth of myoepithelial tumors, as opposed to an infiltrative growth pattern, is due to the low level of secretion of matrix-degrading proteinases and high level of secretion of proteinase inhibitors by myoepithelial cells (6). Epithelial-myoepithelial carcinomas are rarely associated with pain and facial weakness (4,6,7). According to various case reports (2, 4, 7, 9, 10), epithelialmyoepithelial carcinomas of the parotid glands are often painless, without any evidence of mucosal ulceration (4).…”

“…This salivary gland tumor was first described by Donath et al in 1972 and classified as a salivary gland tumor by the world health organization in 1991 (6,7). Epithelial-myoepithelial carcinomas comprise less than 1% of salivary gland tumors, and they mostly affect the parotid gland of adults in their sixth and seventh decades (4). We describe a rare case of a young woman and the clinical, radiographic, and microscopic findings.…”

“…Occasionally, a high-grade or dedifferentiated form may be observed (2,3). This malignant tumor can occur in conjunction with hybrid salivary gland tumors, for example, in combination with adenoid cystic carcinomas and lymphoepithelial carcinomas (4,5). This salivary gland tumor was first described by Donath et al in 1972 and classified as a salivary gland tumor by the world health organization in 1991 (6,7).…”