title: Site-specific morphologic differences in extranodal marginal zone B-cell lymphomas.
abstract: BACKGROUND
  Lymphoepithelial lesions (LELs) are a useful diagnostic feature of extranodal marginal zone B-cell lymphoma (EMZL); however, there is scant literature comparing their frequency and morphology at various sites.
  
  
  OBJECTIVE
  To evaluate any diagnostically useful, site-specific, morphologic patterns in EMZLs.
  
  
  METHODS
  In this retrospective review, we evaluated 136 EMZLs from different sites for LEL pattern and other pathologic differences, including CD43 coexpression and plasma cell component features.
  
  
  RESULTS
  Prominent and destructive LELs were most common in salivary and thyroid gland cases, and LELs were rare to absent in breast, skin, and ocular adnexa cases. An LEL pattern with lymphocytes "stuffing" glandular lumina was seen in lung, thyroid, and salivary gland cases. Monoclonal plasma cells were most common in breast, upper aerodigestive tract, skin, and salivary gland cases. CD43 coexpression was seen in 36% of cases, most commonly in salivary gland, stomach, and upper aerodigestive tract.
  
  
  CONCLUSIONS
  The relative importance of LEL pattern, CD43 coexpression, and clonal plasma cell component in EMZLs is site-dependent, and the differences may aid in the diagnosis of EMZLs at different anatomic sites.
authors.affiliation: Department of Pathology, Minneapolis Veterans Affairs Medical Center, Minneapolis, Minn, USA.
authors.forename: Ajay
authors.initials: A
authors.lastname: Rawal
authors.forename: William G
authors.initials: WG
authors.lastname: Finn
authors.forename: Bertram
authors.initials: B
authors.lastname: Schnitzer
authors.forename: Riccardo
authors.initials: R
authors.lastname: Valdez
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology; D003110:Colonic Neoplasms / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology; D003937:Diagnosis, Differential; D005260:Female; D005770:Gastrointestinal Neoplasms / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology; D006801:Humans; D051917:Leukosialin / Q000378:metabolism*; D016393:Lymphoma, B-Cell / Q000175:diagnosis / Q000378:metabolism* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D010950:Plasma Cells / Q000378:metabolism / Q000473:pathology*; D012189:Retrospective Studies; D012468:Salivary Gland Neoplasms / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology; D012878:Skin Neoplasms / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology; D013274:Stomach Neoplasms / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology; D013964:Thyroid Neoplasms / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology; D001749:Urinary Bladder Neoplasms / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology
chemical_list: D051917:Leukosialin