These tumors consisted of spindle cells that exhibited an arrangement similar to leiomyoma or fibroma. Health, general cancer diagnosis research cancer diagnosis carcinoembryonic antigen genetic aspects cea oncology immunohistochemistry intermediate filament proteins medical research medicine, experimental salivary gland tumors tumor proteins. Myoepithelioma me is a benign salivary gland tumor composed almost exclusively of sheets, islands, or cords of cells with myoepitheliomal differentiation. Epithelialmyoepithelial carcinoma of the parotid gland. The lesions were clinically suspected to be epidermal cyst. More recently, dog1 expression has been reported in salivary gland tumours 68, in particular, as a marker for acinic and intercalated duct cells. It can be present in individuals of a wide age range including children and adults. The initial tumour was a pleomorphic adenoma with epithelial and myoepithelial elements. Locally advanced malignant myoepithelioma of the parotid. A myoepithelial carcinoma, a rare malignant salivary gland neoplasm, arose in a pleomorphic adenoma of the parotid gland. Myoepithelioma is a rare benign tumor of the salivary glands and is usually seen in the parotid gland and the minor salivary glands. Mar 18, 2015 myoepithelioma was recognized as a histologically distinct entity by the world health organization who in 1991.
Design four cases of myoepithelial carcinoma with cytology were retrieved from the archives of the pathology departments of two academic institutes. While myoepithelioma has no specific clinical features, it is accepted pathologically as a distinct entity. It is a benign salivary gland tumor that consists entirely of myoepithelial cells with variable cellular morphologies including spindle, epithelioid, plasmacytoid, or clear cells. They are found in the sweat glands, mammary glands, lacrimal glands, and salivary glands. Pdf plasmacytoid myoepithelioma of the palate in a child. Original research myoepithelioma of the p arotid gland. Oncocytic myoepithelioma and pleomorphic adenoma of the. Two cases of myoepithelioma occurring in the parotid gland were reported. Rare primary lesions that have been known to metastasize to the skin include an adenoid cystic carcinoma, an acinic cell carcinoma, a myoepithelial carcinoma, and adenocarcinoma of the salivary gland, 365370 an adenoid cystic carcinoma of the lacrimal gland, 371 an ameloblastoma, 372 a thymoma, 373 an adrenal carcinoma, 374,375 a pheochromocytoma, 376 and carcinomas of the hypopharynx, 377 nasopharynx, 31,378,379 and larynx. Review and updates of immunohistochemistry in selected.
Malignant myoepithelioma of the parotid gland crissman. Myoepithelioma definition of myoepithelioma by medical. Classically, they are found in the parotid gland or palate. Myoepithelioma is usually a benign tumor arising from neoplastic myoepithelial or basket cells which are found between the basement membrane and the. Losito nsbotti gionna fpasquinelli gminenna pbisceglia m clearcell myoepithelial carcinoma of the salivary glands. Myoepithelioma of salivary glands are very rare, accounting for only 1%1. Report of three cases with varied histomorphology charusheela r gore, nk panicker, ss chandanwale, bikash k singh department of pathology, pad.
Myoepitheliomas of the salivary glands are rare neoplasms accounting for less than 1. As the name suggests, it consists of myoepithelial cells. The recurrence rate is similar to that of the pleomorphic adenoma 1518%. Myoepithelioma occurring in minor salivary glands of oral cavity accounts for 26% of all salivary gland myoepitheliomas and palate being the most common site 69. Myoepithelioma common malignancies mucoepidermoid carcinoma variants adenoid cystic carcinoma carcinoma ex pleomorphic adenoma salivary duct carcinoma mucoepidermoid carcinoma incidence most common malignant salivary gland tumor children and adults major and minor salivary glands p k i id 5th t 6th d d 36. Treatment should be designed as for a benign salivary gland tumor with a margin of normal uninvolved tissue being included within the surgical excision. They present as bulky, bosselated, slowgrowing tumors that maybecomelarge. Histological examination of the second recurrence showed a malignant spindle cell neoplasm with.
Myoepithelioma is more common in adults than in children or adolescents. Myoepithelioma is a benign salivary gland tumor in the head and neck region, accounting for 11. Health, general epithelial tumors care and treatment medicine otolaryngology research parotid glands surgery. Primary myoepithelial carcinoma of palate world journal. Myoepithelioma is a relatively rare form of salivary gland tumor, accounting for less than 1% of all salivary gland neoplasms.
Conservative treatment that preserves the overlaying palatal mucosa while surgically excising the tumor was carried out under general anesthesia, because the. The histological appearance includes solid, myxoid and reticular growth patterns. Myoepithelial tumors of the salivary gland including myoepitheliomas. Myoepithelioma is usually a benign tumor arising from neoplastic myoepithelial or. Since 1943 when sheldon identified them and characterized them as myoepithelioma, less than 100 cases have been reported in the literature. The proportion of myoepitheliomas located in the parotid gland range from 40 to 90% in different reported studies series and of intraoral minor. Myoepithelioma of minor salivary glands a diagnostic challenge. The diagnosis is rendered histopathologically, and it includes the proliferation of myoepithelial cells, without chondroid or myxochondroid stroma and ductal components up to 5% of ductal component is acceptable. Our literature search revealed only one case report of clear cell myoepithelioma of the palate.
Analysis of the clinical relevance of histological classification of. Some studies have suggested that the dog1 protein may be essential for salivary gland secretion with a possible role in salivary gland tumourigenesis 5, 9. Through 1985, only 42 other cases had been reported in the literature. Review and updates of immunohistochemistry in selected salivary. Review of this case and of existing reports indicates that myoepitheliomas exhibit a wide range of biological behavior that seems to correlate with their histological appearance. The aim of this study is to present and discuss the clinical, morphological and immunohistochemical. The tumor cells of the two cases likewise contained myofilaments and gave a positive result for the s. Review and updates of immunohistochemistry in selected salivary gland and head and neck tumors shaobo zhu, md.
Two tumours presented as intraoral lesions and eight were located in the parotid gland. Histological examination of the second recurrence showed a malignant spindle cell. Solid proliferation of ovoid, spindled, histiocytoid or epithelioid cells with abundant eosinophilic syncytial cytoplasm and little stroma. Myoepithelioma is a rare neoplasm of the salivary glands, generally occurring in the parotid gland and less often in the minor accessory salivary gland of the oral cavity. Myoepithelioma me is a rarely encountered tumor of salivary gland accounting for about 1% of all salivary gland tumors. Salivary gland malignant myoepithelioma nagao 1998 cancer. Immunohistochemistry is a useful tool for diagnosing salivary gland and head and neck tumors. Myoepithelioma of parotid gland presenting as infraauricular. Myoepithelial carcinoma, also know as malignant myoepithelioma, is rare in the salivary gland, and its cytologic features have rarely been reported. Myoepithelial carcinoma is a rare malignant cancerous tumor that usually occurs in the salivary glands in the mouth, but can also occur in skin and soft tissues. Clear cell myoepithelioma arising from the minor salivary glands of hard palate is a rare entity.
A similar tumor type may be found in the tongue, referred to as ectomesenchymal chondromyxoid tumor. Cytology of myoepithelial carcinoma of the salivary gland. These may be positive for alpha smooth muscle actin and can contract and expel the secretions of exocrine glands. Salivary gland myoepithelioma with focal capsular invasion. Myoepitheliomas mes are rare tumors of the parotid gland. Myoepithelioma of the salivary glands was first classified by sheldon in 1943. Nov 18, 2016 myoepithelial carcinoma is a rare malignant cancerous tumor that usually occurs in the salivary glands in the mouth, but can also occur in skin and soft tissues. Mar 11, 2014 myoepitheliomas of the salivary glands are rare neoplasms accounting for less than 1. They most commonly affect the major and minor salivary glands with the parotid gland being the most common, approximately 40%. Report of 23 cases twelve of these were located within the parotid gland and the submandibular gland and intraoral minor salivary glands accounted for five each. Solid nonmyxoid, myxoid pleomorphic adenomalike, reticular canalicularlike or mixed patterns of myoepithelial cells with no ductal differentiation.
Pdf minimally invasive surgery in a pediatric palatal. Plasmacytoid myoepithelioma of minor salivary glands. The plasmacytoid cell type appears to have a predilection for the oral cavity, especially the palate. Myoepithelioma is a rare disease in the salivary gland. Myoepithelial carcinoma malignant myoepithelioma of the. Although they are an important element in many salivary gland tumors, 1 pure myoepitheliomas are rare, accounting for of all salivary gland tumors.
We report two patients with myoepithelioma of parotid gland presenting as infraauricular subcutaneous mass. Four cases of myoepithelial carcinoma with cytology were retrieved from the archives of the pathology departments of two academic institutes. Though they were first identified long back, still their histopathologic features and immunohistochemistry ihc profile are not well characterized and there is no definitive criterion for this tumor with complex and varied features remaining a major barrier. Myoepitheliomas are most common in young adults between the ages of 30 and 50 and there are very few cases reported in. Myoepithelial cells in these cases constitute the basal cell layer of an epithelium that harbors the epithelial progenitor. Salivary gland malignant myoepithelioma nagao 1998. Presence of a tumor mass on the face or in the mouth. The salivary glands comprise the three paired major glands the parotid, the submandibular and sublingual and the minor glands located in the palate, lips, buccal mucosa.
The most common site is parotid gland with a few arising in minor salivary glands of the oral cavity and palate. Dec 12, 2011 myoepithelioma is a rare benign tumor of the salivary glands and is usually seen in the parotid gland and the minor salivary glands. Malignant myoepithelioma of salivary glands is a rare neoplasm. Well circumscribed dermal lesions, not connected to epidermis, may extend into superficial subcutis either composed of. Myoepithelioma is a benign salivary gland neoplasm, locally invasive and uncommon in children. We present here a case of a malignant myoepithelioma of the parotid gland, confirmed by electron microscopy, that was locally aggressive and eventually metastasized. Only a few case reports describing ct imaging features of me have been published. Patil medical college, hospital and research centre, dr. Oncocytic change in myoepithelial cells in mes and pas can cause pitfalls in the differential diagnosis of salivary gland tumours. Myoepitheliomas are tumors arising from myoepithelial cells mainly or exclusively.
Myoepithelioma is a rare but wellcharacterized group of tumours, among which myoepithelioma of the salivary glands is the best known. Only 1% of all salivary gland neoplasms are myoepitheliomas. Myoepithelial carcinoma an overview sciencedirect topics. Myoepithelioma is a wellcircumscribed or encapsulated tumor. Myoepithelioma was recognized as a histologically distinct entity by the world health organization who in 1991.
It was once considered to be a type of pleomorphic adenoma pa, but myoepitheliomas are today believed to be relatively aggressive tumors. A 56yearold man was admitted to the ent department complaining of a painless soft. There have been only four cases of myoepithelioma in children and adolescents reported in the englishlanguage. Read biphasic myoepithelioma of parotid gland with collagenous crystalloids, histopathology on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. Age of presentation ranges from 2060 years of age, and parotid gland, and accessory salivary glands are the main site of occurrence. The tumors mostly present as asymptomatic, slowly progressive masses over a period of months to years in the patient with average age in the fourth decade 1. Grossly they may have a solid, white or yellow glistening cut. The diagnosis was made on the basis of characteristic ultrastructural as well as immunohistochemical findings. A myoepithelioma neoplasm is almost entirely composed of myoepithelial cells and is most frequently located in the parotid gland and in the minor salivary glands of the hard palate. These tumors can occur in most of the glandular structures like salivary glands, breast and sweat glands of the skin. The diagnosis is rendered histopathologically, and it includes the.
An 8yearsold female patient visited our clinic with a chief complaint of a painless swelling on the palate. All the tumors were excised surgically with a tumor free surgical margin in seven. Myoepithelioma of the head and neck, also myoepithelioma, is a salivary gland tumour of the head and neck that is usually benign. Asapplied in the salivary gland context, a number of morphologically different subtypes of myoepithelioma are describedwith90%consistingofspindleshaped or polygonal cells. Malignant myoepithelioma of salivary gland is very rare, accounting for only 0. Vimentin and s100 protein are very sensitive but nonspecific immunohistochemical markers of neoplastic myoepithelium. Capsules are generally better developed in tumors of the major glands, whereas those arising in the palate or other minor salivary or seromucinous gland sites are circumscribed but not usually encapsulated. They account for less than 1% of salivary gland tumors, only rarely undergo malignant transformation 0. Approximately 66% of these tumors occur in a part of the salivary gland, known as the parotid gland. Myoepitheliomas mostly occur in salivary glands, as well as in breast, skin, and lung. Malignant myoepithelioma mme of the salivary gland, also known as. The tumor is composed exclusively of myoepithelial cells that show spindle, plasmacytoid, and clear cell morphology.
Neoplastic cells with myoepithelial differentiation are often present in both benign and malignant salivary glands neoplasms. Malignant myoepithelioma of the salivary gland is discussed in terms of its clinical behaviour, morphological features and the frequent preexistence of a pleomorphic adenoma. We herein report an extremely rare case of this tumor with lipomatous. Most of the cases of palatal myoepitheliomas reported so far are either plasmacytoid or spindle cell type. The salivary glands include paired major glands pa. The topic malignant myoepithelioma of salivary gland you are seeking is a synonym, or alternative name, or is closely related to the medical condition myoepithelial carcinoma of salivary gland. Characterisation of dog1 expression in salivary gland. The most common location of myoepithelioma in the head and neck region are parotid gland 40% and the palate 2%. Myoepithelioma is a rare benign salivary gland tumour, localized most frequently in the parotid and in minor intraoral salivary glands. Myoepitheliomas are rare, benign neoplasms affecting predominantly parotid gland and to a lesser extent minor salivary glands. The study comprised six female and four male patients aged 1463 years mean age 38. Salivary gland tumors sgts are rare neoplasms accounting for 0. The present paper describes the clinical and pathologic features of a benign myoepithelioma of the parotid gland.