Myoepithelioma is usually a benign tumor arising from neoplastic myoepithelial or basket cells which are found between the basement membrane and the. Myoepitheliomas are most common in young adults between the ages of 30 and 50 and there are very few cases reported in. 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. Salivary gland myoepithelial carcinoma mc or malignant myoepithelioma is a rare entity.
Myoepitheliomas mes are rare tumors of the parotid gland. Only a few case reports describing ct imaging features of me have been published. Myoepithelioma is a benign tumor of the oral cavity, arising predominantly from major and minor salivary glands, and accounting for 11. Cutaneous myoepithelial carcinoma is a tumor that can occasionally show ewsr1 gene rearrangement. They are most commonly found in the parotid gland and palatal area 1. Myoepithelioma of minor salivary gland an immunohistochemical. Myoepithelioma are uncommon, representing approximately 1% of salivary gland tumors. These tumors can occur in most of the glandular structures like salivary glands, breast and sweat glands of the skin. It is a benign salivary gland tumor that consists entirely of myoepithelial cells with variable cellular morphologies including spindle, epithelioid, plasmacytoid, or clear cells. The number of case reports is increasing as pathologists have become more aware.
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. Myoepithelioma is a rare neoplasm of the salivary glands, generally occurring in the parotid gland and less often in the minor accessory salivary gland. Benign myoepitheliomas are mainly composed of myoepithelial cells, which are ectodermally derived cells located between the basal surface of acinar units, basement membrane, and surrounding intercalated duct. Myoepithelioma was recognized as a histologically distinct entity by the world health organization who in 1991. The tumor cells of the two cases likewise contained myofilaments and gave a positive result for the s. Myoepithelioma of the parotid gland, pathology international. Only three cases of sinonasal myoepithelioma have been reported in the literature. Historically, they were initially classed as a subtype of pleomorphic adenoma, but were recognised as a separate tumour class by the world health organisation in. Only 1% of all salivary gland neoplasms are myoepitheliomas. Myoepithelioma of salivary glands are very rare, accounting. 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.
Sep 24, 2014 soft tissue myoepithelial carcinoma and myoepithelioma are rare entities, part of myoepithelial tumors. Jul 11, 2008 myoepithelioma is a rare benign neoplasm. Myoepithelioma is a rare and unusual salivary gland tumor that can be considered a monomorphic variant of pleomorphic adenoma. Myoepithelioma of a minor salivary gland of the cheek. The most common site is parotid gland with a few arising in minor salivary glands of the oral cavity and palate.
Salivary gland myoepithelial carcinoma springerlink. To the best of our knowledge, such an association has never been reported in the literature. Mar 27, 2018 myoepithelioma of salivary gland is an uncommon benign tumor typically arising in the major salivary glands. It accounts for myoepithelioma and related lesions. Pdf malignant myoepitheliomas myoepithelial carcinomas are uncommon, and we know of only 29 reported cases. The initial tumour was a pleomorphic adenoma with epithelial and myoepithelial elements. Clinically it resembles like other tumour masses and thus posed challenge to clinician and pathologist. We describe some unusual histological features associated with onococytic metaplasia in benign myoepithelial cellderived salivary gland tumours, hoping to help to avoid the overdiagnosis of malignancy. Subsequently the tumour recurred twice and was characterised by invasion of the mandible.
It was once considered to be a type of pleomorphic adenoma pa, but myoepitheliomas are today believed to be relatively aggressive tumors. They were incorporated into the world health organization classification of soft tissue tumors in 2002. Objective to analyze the importance of unique cytoarchitectural patterns and the immunohistochemical profile in the diagnosis of myoepithelial carcinomas. Oncocytic myoepithelioma and pleomorphic adenoma of the. Objective to analyze the importance of unique cytoarchitectural patterns and the immunohistochemical profile in the diagnosis of myoepithelial carcinomas design retrospective case analysis setting tertiary cancer center patients a total of 51 patients with myoepithelialrich carcinomas diagnosed over a 14year period were studied for demographic data and tumor histologic. Myoepithelioma of salivary glands are very rare, accounting for only 1%1. Salivary gland myoepithelioma with focal capsular invasion. Cutaneous myoepithelial carcinoma with disseminated. Pdf myoepithelioma of minor salivary glands a diagnostic. Myoepitheliomas of minor salivary glands accounts to only 1. As the name suggests, it consists of myoepithelial cells.
The aim of this study was to describe and characterize the ct findings of mes of the parotid. Diagnosis of myoepithelioma through light microscopy is possible and immunohistochemistry is done to facilitate the diagnosis. Myoepithelioma of the head and neck, also myoepithelioma, is a salivary gland tumour of the head and neck that is usually benign. 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. By means of these two case reports, we have attempted to scrutinize this entity. The peak incidence is in the sixth and seventh decades.
A final diagnosis of salivary gland myoepithelioma with focal capsular invasion was made, and the case was regarded as a myoepithelial tumor of uncertain malignant potential. Myoepithelioma is rare benign neoplasm, usually involves salivary glands and very less often seen in minor salivary glands of nose. Mc may arise from preexisting benign lesions, such as. Wed like to understand how you use our websites in order to improve them. Myoepithelioma is rare benign tumors representing about the 1% of all the salivary gland tumors. Such lesion shows a varied pattern of morphological growth, it may be solid, myxoid or reticular. The diagnosis is rendered histopathologically, and it includes the. The 2 most common sites of occurrence are the parotid gland 40% and the. Malignant myoepithelioma mme of the salivary gland, also known as myoepithelial carcinoma, is rare and its biologic. Mc usually presents as a slowgrowing painless mass arising in the parotid gland, but may involve other salivary glands.
Mar 18, 2015 myoepithelioma was recognized as a histologically distinct entity by the world health organization who in 1991. Such a rare case of myoepithelioma in salivary glands present at an unusual location around the left orbit is presented here. It is a benign tumor that is composed almost exclusively of myoepithelial cells. Myoepithelioma me is a benign salivary gland tumor composed almost exclusively of sheets, islands, or cords of cells with myoepitheliomal differentiation. 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.
Maria della misericordia, 33100 udine, italy b department of oral pathology, faculty of medicine, university of. Pure accounting for less than 1% of all salivary gland tumors. Formerly considered a variant of pleomorphic adenoma. Myoepitheliomas are rare salivary gland tumours which make up between 1 and 1. A myoepithelial carcinoma, a rare malignant salivary gland neoplasm, arose in a pleomorphic adenoma of the parotid gland. Myoepitheliomas are rare benign neoplasias of the salivary gland, more commonly found in the parotid1, 2, being. Myoepithelioma is a benign salivary gland tumor in the head and neck region, accounting for 11.
Myoepithelioma is usually a benign tumor arising from neoplastic myoepithelial or basket cells which are found between the basement membrane and the basal. Cutaneous myoepithelial carcinoma is a rare malignant adnexal neoplasm with metastatic potential that can present in the skin. Myoepithelioma is a rare neoplasm that accounts for fewer than 1% of all salivary gland tumors. However, other rare sites like the lips, inner lining of the. Pdf malignant myoepithelioma of the salivary glands. 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. Approximately 66% of these tumors occur in a part of the salivary gland, known as the parotid gland. Jan, 2010 myoepithelial cells are usually seen between epithelial cells and basal cells in intercalated ducts and acini of exocrine glands. About 60% to 70% of mca develop in a benign mixed tumor. We report two patients with myoepithelioma of parotid gland presenting as infra. It can be present in individuals of a wide age range including children and adults the cause of formation of salivary gland myoepithelioma is not wellunderstood, although certain chromosomal alterations and gene mutations have been. Rare benign tumor composed only of myoepithelial cells.
Classically, they are found in the parotid gland or palate. Myoepithelioma of minor salivary glands a diagnostic. Pdf spindle cell myoepithelioma of the parotid gland. Patients a total of 51 patients with myoepithelialrich. 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.
The diagnosis was made on the basis of characteristic ultrastructural as well as immunohistochemical findings. Here we present an exceptional case of myoepithelial carcinoma and myoepithelioma association. Myoepithelioma is a benign salivary gland neoplasm, locally invasive and uncommon in children. Introduction myoepithelioma is defined as a benign tumour composed of myoepithelial cells. The most common site of involvement is parotid gland, followed by palate in the oral cavity. Myoepitheliomas of salivary glands are extremely rare, comprising approximately only 11. 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. It becomes very difficult to diagnose due to its varied presentation and propensity for malignant transformation. Myoepithelioma is a rare benign tumor of the salivary glands and is usually seen in the parotid gland and the minor salivary glands.
A similar tumor type may be found in the tongue, referred to as ectomesenchymal chondromyxoid tumor. Malignant myoepithelioma is a rare salivary gland carcinoma that might be confused with other neoplastic lesions, including carcinoma and sarcoma. The lesions were clinically suspected to be epidermal cyst. Myoepithelioma of parotid gland presenting as infra. Myoepitheliomas are rare, benign neoplasms affecting predominantly parotid gland and to a lesser extent minor salivary glands. Myoepithelioma have been described most commonly in salivary gland and accounts for 1% of all tumors developing in the salivary gland. Myoepithelioma of salivary gland is an uncommon benign tumor typically arising in the major salivary glands. Two cases of myoepithelioma occurring in the parotid gland were reported. Robiony a a department of maxillofacial surgery, faculty of medicine, university of udine, piazzale s. Myoepitheliomas of the salivary gland are very rare tumors, with an incidence of less than 1% of all salivary gland tumors.
In this report, we discuss the histologic criteria required to diagnose malignancy in salivary gland myoepithelial tumors. The vast majority are benign, with only rare malignant examples reported in the literature. Histological examination of the second recurrence showed a malignant spindle cell. Myoepithelial carcinoma malignant myoepithelioma of the. Revised who histological classification of salivary gland tumours 171. Myoepithelioma is a wellcircumscribed or encapsulated tumor.
The histological appearance includes solid, myxoid and reticular growth patterns. It differs from the pleomorphic adenoma because it does not bear any ductal component5. Oncocytic change in myoepithelial cells in mes and pas can cause pitfalls in the differential diagnosis of salivary gland tumours. Myoepithelioma of the head and neck, also myoepithelioma, is a salivary gland tumour of the head and neck that is usually benign as the name suggests, it consists of myoepithelial cells. Salivary gland neoplasms composed exclusively of myoepithelial cells myoepitheliomas are unusual and intriguing. The tumor is composed exclusively of myoepithelial cells that show spindle, plasmacytoid, and clear cell morphology. Combined myoepithelial carcinoma and myoepithelioma in soft. Excision with negative margins and close followup is recommended for cutaneous myoepithelial carcinoma. Article pdf available in journal of oral and maxillofacial pathology. 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. This tumour may be particularly locally aggressive, but its clinical and biological features are not yet fully understood. Myoepithelioma of minor salivary glands a diagnostic challenge. They most commonly affect the major and minor salivary glands with the parotid gland being.
Plasmacytoid myoepithelioma of minor salivary glands. Myoepithelioma is uncommon and account for only 1% of all salivary gland tumours. Myoepithelioma occurs in most major and minor salivary gland tissues, and it is generally a biologically benign lesion. Since 1943 when sheldon identified them and characterized them as myoepithelioma, less than 100 cases have been reported in the literature.
1546 859 1580 358 626 281 1043 1205 461 509 1102 280 874 547 192 1312 1410 1582 1431 473 610 936 1352 403 338 973 1425 643 373 310 610 524 1072 485