Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 429 (1996), S. 139-147 
    ISSN: 1432-2307
    Keywords: HIV ; Parotid gland ; Lymphoepithelial cyst ; Lymphoepithelial lesion ; Sjögren disease
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Whether lymphoepithelial cysts in the parotid glands in HIV-infected patients develop from pre-existing salivary gland inclusions in intraparotid lymph nodes or from a lymphoepithelial lesion of salivary parenchyma is unclear. To examine their pathogenesis we performed a histological and immunohistochemical study of salivary specimens from 100 AIDS patients in different disease stages. There is a continuous morphological spectrum of changes within the salivary parenchyma, starting with lymphoid stroma infiltration and evolving to characteristic lymphoepithelial duct lesions with a immunohistochemically proven basal cell proliferation and to fully developed ductal cysts. Involvement of myoepithelial cells — postulated in comparable Sjögren-associated duct lesions — is excluded immunohistochemically. Computer-assisted 3-D reconstructions confirm an association of the cysts with the intralobular duct system. Our study disproves the prevailing hypothesis, which suggests that the lymphoid cell compartment of HIV-associated lymphoepithelial cysts stems from pre-existing intraparotid lymph nodes. The results demonstrate that a secondary lymphatic infiltration of salivary parenchyma provokes a lymphoepithelial lesion of striated ducts with basal cell hyperplasia. The frequent progression to a multifocal cystic lymphoepithelial lesion may be supported by ductal compression through a high degree of lymphofollicular hyperplasia in early disease.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1432-2307
    Keywords: Key words Salivary glands ; Lymphoepithelial lesion ; Sjögren disease ; Metaplasia ; Cytokeratin filaments
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  It is not clear, whether the so-called basal cells of the salivary striated ducts are an independent cell-type distinct from myoepithelial cells, making characterization of the cell proliferation typical of the duct lesions in Sjögren-type sialadenitis/benign lymphoepithelial lesion (BLEL) difficult. An immunohistochemical investigation including different cytokeratin subtypes, α-actin, Ki-67 and Bcl-2 was directed at the epithelial cytoskeleton in normal parotid parenchyma (n=8), BLEL (n=12), HIV-associated lymphoepithelial cysts (n=8) and palatine tonsils (n=8). There are profound morphological and functional differences between basal and myoepithelial cells in the normal salivary duct. Development of duct lesions in BLEL arises from basal cell hyperplasia of striated ducts with aberrant differentiation into a multi-layered and reticulated epithelium, characterized by profound alteration of the cytokeratin pattern. This functionally inferior, metaplastic epithelium is similar to the lymphoepithelial crypt epithelium of palatine tonsils. The often postulated participation of myoepithelial cells in duct lesions of Sjögren disease/BLEL cannot be supported. We regard the designations lymphoepithelial lesion and lymphoepithelial metaplasia as the most appropriate.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1432-1963
    Keywords: Schlüsselwörter Speicheldrüsen ; Lymphoepitheliale Gangläsion ; Morbus Sjögren ; Marginalzonen-B-Zell-Lymphom ; Lymphoepitheliale Zyste ; Keywords Salivary glands ; Lymphoepithelial duct lesion ; Sjögren's syndrome ; Marginal zone B-cell lymphoma ; Lymphoepithelial cyst
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Abstract Several salivary gland diseases present with the histomorphological features of a lymphoepithelial lesion with or without cyst formation. Some of the most important differential diagnoses (Sjögren‘s syndrome, marginal zone B-cell lymphoma, HIV-associated cystic lymphoepithelial lesion) are systemic diseases and require further investigation and therapy. However, in small biopsy specimens and in cases without relevant clinical information an exact diagnosis may be difficult to obtain. We have recently determined that the characteristic lymphoepithelial duct lesions develop by proliferation of basal cells of striated ducts, while we could not confirm the previously postulated participation of myoepithelial cells (“epimyoepithelial lesion/sialadenitis”). Although these duct lesions are typical of Sjögren's syndrome, they manifest in several diseases of salivary glands, exhibiting characteristic patterns concerning frequency and localization. This review discusses the most important lymphoepithelial diseases of salivary glands with respect to clinical presentation and histomorphology. Particular emphasis is placed on the lymphoepithelial duct lesions.
    Notes: Zusammenfassung Der histomorphologische Befund einer lymphoepithelialen Speicheldrüsenläsion mit oder ohne Zystenbildung kann auf mehreren, ätiologisch unterschiedlichen Speicheldrüsenerkrankungen beruhen. Eine eindeutige Diagnosestellung ist dabei wichtig, da einige Differenzialdiagnosen (Morbus Sjögren, Marginalzonenlymphom, HIV-assoziierte zystische lymphoepitheliale Läsion) als Ausdruck einer Systemerkrankung eine weiter gehende Diagnostik und Therapie erfordern. Eine eindeutige Zuordnung ist allerdings gerade bei kleinen bioptischen Exzidaten und mangelnder klinischer Information häufig schwierig. Wir konnten zeigen, dass die charakteristischen Speichelgangläsionen bei Morbus Sjögren auf einer Proliferation von Basalzellen der Streifenstücke beruhen, während eine früher häufig postulierte Beteiligung von Myoepithelzellen (“epimyoepitheliale Läsion/Sialadenitis”) nicht vorliegt. Diese Gangläsionen gelten zwar als charakteristisch für Morbus Sjögren, treten aber auch bei weiteren Speicheldrüsenerkrankungen auf und zeigen dabei diagnostisch verwertbare Muster bezüglich Häufigkeit, Grad der Ausprägung und Lokalisation. In der vorliegenden Übersicht werden die wichtigsten lymphoepithelialen Speicheldrüsenerkrankungen hinsichtlich klinischer und histomorphologischer Charakteristika gegenübergestellt, wobei das besondere Augenmerk dem differenzialdiagnostischen Stellenwert der Gangläsionen gilt.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Springer
    European archives of oto-rhino-laryngology and head & neck 251 (1994), S. 214-217 
    ISSN: 1434-4726
    Keywords: Sjögren's syndrome ; Malignant lymphoma ; Magnetic resonance imaging
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract In the past few years a variety of papers on magnetic resonance imaging (MRI) of the salivary glands have been published, mainly focusing on the evaluation of salivary gland tumors. More recently, non-tumorous lesions have also been examined with this imaging technique. In Sjögren's syndrome (SS) a characteristic inhomogeneous pattern with a “honeycomb-like” appearance of the parotid gland tissue has been shown in the T2-weighted sequence. This study shows MRI findings in four cases of intraglandular lymphoma occurring in patients with SS. Four patients with suspected lymphomas were examined with MRI, following which all lesions were either biopsied or removed. This enabled us to correlate clinical, radiological and pathological findings. Results indicate that MRI is a useful imaging tool in the detection of intraglandular lymphatic infiltrates, although it is not possible to distinguish morphologically between a localized lymphatic infiltrate and an early stage malignant lymphoma. Nevertheless, MRI is considered to be a valuable non-invasive method for deciding whether or not to perform a biopsy. Due to the excellent soft tissue differentiation obtained, it is also helpful for the surgeon to plan and perform a successful biopsy with minimal risk to the facial nerve.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...