The cell with a thousand faces: Detection of myoepithelial cells and their contributions in the cytological diagnosis of salivary gland tumors

Abstract

Myoepithelial cells are an important component of salivary gland tumors and are partly responsible from the diverse histology of them. In this study, we focus on the myoepithelial cell differentiation by using cytological morphology in a various types of salivary gland tumors especially with regard to their contribution to the diagnosis. The relation of myoepithelial cells with stromal matrix and the associated epithelial cells were evaluated. Cytologic slides of one hundred and forty one benign and twenty malignant salivary gland tumors were examined for identification of morphologically different myoepithelial cells such as; spindle-stellate, polygonal-epitheloid, plasmacytoid, basal and clear types. The best examples of myoepithelial cells were detected in pleomorphic adenomas, in some monomorphic adenomas and in the adenoid cystic carcinoma cases. Most of the pleomorphic adenomas were composed more than one type of myoepithelial cells and epitheloid-spindle cell combination was frequent. Basal and clear cell types of myoepithelial cells closely resembled the epithelial cells and their identification was relatively difficult. Identification of myoepithelial cell types was easier when they were associated with stromal matrix material and stood as a secondary layer around tubule-forming epithelial cells. Myoepithelial cell components of various salivary gland tumors may be quite different and identification of myoepithelial cell types may pose difficulties. A confident cytologic identification of myoepithelial cells may be critical part of diagnosing salivary gland tumors.

NOD and NOR mice exhibit comparable development of lacrimal gland secretory dysfunction but NOD mice have more severe autoimmune dacryoadenitis

“…Myoepithelial cells (MEC) are stellate-shaped cells with long slender processes that form a basket-like network around LGAC. These cells express α-smooth muscle actin (SMA), a marker for MECs, which can contract and thereby assist the secretory function of exocrine glands (Avci et al, 2012; Dartt, 2009; Gudjonsson et al, 2005). MECs express abundant neurotransmitter receptors such as muscarinic receptors, suggesting that these cells are responsive to the same neural stimulation responsible for inducing secretion of LG fluid (Lemullois et al, 1996).…”

Clear cell changes in salivary gland neoplasms: A 20-year retrospective study

“…In the context of predicting clear cell change, one question arose of which type of salivary gland tumor cell was most likely to exhibit clear cell change. Myoepithelial cells have been observed to rarely show clear cell change due to glycogen accumulation (1,8,9). In addition, the clear cells noted in MEC have been found to be most similar in immunohistochemical profile to the intermediate cells in this tumor (2).…”

Myoepithelial Cell-Rich Pleormorphic Adenoma of Minor Salivary Gland of Parapharyngeal Space

“…Detection of myoepithelial differentiation both in aspiration cytology and histologic examination can also help diagnosing a tumor as of salivary gland type [12]. The proteins SMA, calponin, CD29, S100, and P63, which are present from the earliest stage of maturation of myoepithelial cell are the most valuable for their diagnosis [13].…”