title: t(11;18)(q21;q21) in extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue in stomach: a study of 48 cases.
abstract: Gastric extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MZL-MALT) is speculated to be immune mediated and is notable for responding to treatment by Helicobacter pylori eradication. However, the gastric MZL-MALT with t(11;18)(q21;q21) has been shown to be resistant to treatment by H. pylori eradication. We studied the molecular, immunohistochemical, and histological aspects of 48 cases of gastric MZL-MALT and used a reverse transcription real-time PCR assay to assess the presence of a t(11;18)(q21;q21) in formalin-fixed, paraffin-embedded tissue. Florescence in situ hybridization for t(11:18)(q21;q21) was used to confirm the real-time PCR results. Three distinct morphological subtypes were recognized: monocytoid, small lymphocytic, and plasmacytoid. Morphology, immunophenotype, and immunoglobulin heavy chain (IgH) gene rearrangement were correlated with the results of the t(11:18)(q21;q21) assay. Of the 48 analyzed cases, 15 (31%) were positive for t(11;18)(q21;q21) and 33 (69%) were monoclonal for IgH gene rearrangement. Of the 15, 13 (87%) cases with t(11;18)(q21;q21) translocation showed IgH gene rearrangement by PCR. Of the 33 t(11;18)(q21;q21)-negative cases tested, 20 cases (61%) showed IgH gene rearrangement. The 15 t(11;18)(q21;q21) translocation-positive cases had either monocytoid (12 of 15) or small lymphocytic morphology (3 of 15). Aberrant expression of CD43 was observed in 8 of 15 (53%) t(11;18)(q21;q21)-positive cases and 21 of 31 (68%) t(11;18)(q21;q21)-negative cases. Our data show that t(11;18)(q21;q21)-positive MZL-MALTs frequently show monocytoid morphology, less often small lymphocytic morphology, and not purely plasmacytoid morphology. Identification of a t(11;18)(q21;q21) by reverse transcription real-time PCR is highly specific for MZL-MALT and helps in the diagnosis of MZL-MALT. Studying the correlation between this translocation and morphological features may increase our understanding of the role of this translocation in the pathogenesis and the clinical behavior of gastric MZL-MALT.
authors.affiliation: Division of Molecular Pathology, Department of Scientific Laboratories, Armed Forces Institute of Pathology, Washington DC 20306-6000, USA. guanghua.wang@afip.osd.mil
authors.forename: Guanghua
authors.initials: G
authors.lastname: Wang
authors.forename: Aaron
authors.initials: A
authors.lastname: Auerbach
authors.forename: Minqi
authors.initials: M
authors.lastname: Wei
authors.forename: Nancy
authors.initials: N
authors.lastname: Dow
authors.forename: Todd S
authors.initials: TS
authors.lastname: Barry
authors.forename: LeAnn
authors.initials: L
authors.lastname: Hodge
authors.forename: Daniel
authors.initials: D
authors.lastname: Schaffer
authors.forename: Leslie H
authors.initials: LH
authors.lastname: Sobin
authors.forename: Nadine S
authors.initials: NS
authors.lastname: Aguilera
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002880:Chromosomes, Human, Pair 11 / Q000235:genetics*; D002887:Chromosomes, Human, Pair 18 / Q000235:genetics*; D005260:Female; D015326:Gene Rearrangement, B-Lymphocyte, Heavy Chain / Q000235:genetics; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D051917:Leukosialin / Q000096:biosynthesis; D018442:Lymphoma, B-Cell, Marginal Zone / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013274:Stomach Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D014178:Translocation, Genetic
chemical_list: D051917:Leukosialin