title: [Plasma cell myeloma in the stomach?].
abstract: The detection of a diffuse infiltrate of heterogeneous small B-cells in the lamina propria mucosae invading the epithelium and destroying the glandular tissue by discrete aggregates of three or more marginal zone B-cells above the basal membrane (so-called lymphoepithelial lesions) is suspicious of a mucosa-associated lymphoid tissue (MALT) lymphoma of the stomach. The demonstration of a monoclonal B-cell population by immunohistochemistry, in situ hybridization or PCR excludes a benign lymphatic lesion. In the differential diagnosis with other small B-cell lymphomas in the stomach, a panel of five different immunohistochemical markers is useful to diagnose a small lymphocytic lymphoma (CD5 and CD23 positive), a mantle cell lymphoma (CD5 and cyclin D1 positive) or a follicular lymphoma (BCL2 and CD10 positive). The presence of the translocation t(11;18)(q21;q21) or the API2/MALT1 rearrangement could give further information about the clinical course and the prognosis of a gastric MALT lymphoma.
authors.affiliation: Institut für Pathologie, Klinikum Aschaffenburg, Am Hasenkopf, 63739, Aschaffenburg, Deutschland, tiemo.katzenberger@klinikum-aschaffenburg.de.
authors.forename: T
authors.initials: T
authors.lastname: Katzenberger
authors.forename: O
authors.initials: O
authors.lastname: Al-Taie
authors.forename: W
authors.initials: W
authors.lastname: Fischbach
authors.forename: M
authors.initials: M
authors.lastname: Eck
mesh_terms: D000368:Aged; D001402:B-Lymphocytes / Q000473:pathology; D003937:Diagnosis, Differential; D005260:Female; D005753:Gastric Mucosa / Q000473:pathology; D006801:Humans; D017403:In Situ Hybridization; D018442:Lymphoma, B-Cell, Marginal Zone / Q000235:genetics / Q000473:pathology*; D025202:Molecular Diagnostic Techniques; D009101:Multiple Myeloma / Q000235:genetics / Q000473:pathology*; D011379:Prognosis; D013274:Stomach Neoplasms / Q000235:genetics / Q000473:pathology*