Spindelzelliges Myoepitheliom der kleinen Speicheldrüsen mit ausgeprägter lipomatöser Komponente

Zusammenfassung

Unter den benignen Speicheldrüsentumoren stellen Myoepitheliome eine seltene Entität dar. Sie kommen vorwiegend in den großen Speicheldrüsen vor. Die Tumore leiten sich von den umkleidenden Myoepithelzellen der Speicheldrüsenazini ab und stellen eine Differenzialdiagnose zum malignen Myoepitheliom (myoepitheliales Karzinom) sowie verschiedenen anderen epithelialen und mesenchymalen Speicheldrüsentumoren dar.

Eine Lipomatosis des Tumorparenchyms in Form isolierter Fettgewebsinseln oder verstreut liegender Lipozyten ist in pleomorphen Adenomen oder Myoepitheliomen der großen Speicheldrüsen in ganz vereinzelten Fallberichten beschrieben, jedoch in kleinen Speicheldrüsen unbekannt.

Wir berichten erstmals über ein Myoepitheliom der palatinalen kleinen Speicheldrüsen eines 38-jährigen Patienten, welches eine lipomatöse Komponente aufweist.

Abstract

Myoepitheliomas of the salivary glands are rare benign tumors composed of spindle-shaped myoepithelial cells, but may show plasmacytoid, epitheloid and clear cell-types that principally exhibit myoepithelial but not ductal differentiation. These tumors are mainly located in the major salivary glands and have sometimes abundant, acellular, mucoid or hyaline stroma but lack chondroid and myxochondroid foci, probably representing the one end of the spectrum of pleomorphic adenoma. Lipomatosis in the form of isolated small islands or scattered single lipocytes, is quite uncommon, and a large amount of adipose tissue in a pleomorphic adenoma and myoepithelioma is a rarity and only described in major salivary glands.

We present the case report of a 38-year old man with a myoepithelioma of the minor palatinal salivary glands with extensive lipomatosis as an example of this rare phenomen.

Schlüsselwörter

Myoepitheliom · Speicheldrüse · lipomatöse Metaplasie

Key words

Myoepithelioma · salivary gland · lipomatosis

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