title: E-cadherin expression in thymomas.
abstract: For the purpose of investigating the pattern of E-cadherin (E-CD) expression in thymomas, 72 cases were immunostained using monoclonal antibody (HECD-1) and microwave-enhanced immunohistochemical method on formalin-fixed, paraffin-embedded tissue sections. The thymomas were classified according to modified Müller-Hermelink classification. The spindle-shaped, medullary type tumor epithelial cells in medullary (3 cases) and composite type (20 cases) thymomas rarely expressed E-CD except in focal areas showing microcystic change observed in 8 cases. Meanwhile, the cohesive epithelioid tumor cells in every case of well-differentiated thymic carcinomas (WDTC) (29 cases) expressed E-CD. The epithelial cells in cortical type (13 cases) expressed stronger E-CD compared with those of organoid type (7 cases). In cases of WDTC admixed with cortical type, we observed increasing expression of E-CD as the tumor epithelium forms cohesive sheets. We could not find any loss of E-CD expression in invasive foci of the 11 cases of high-staged WDTC examined. Since the results of our study show a strong correlation between E-CD expression and epithelioid morphology of the tumor, E-CD seems to play a major role as a morpho-regulatory factor rather than as a suppressor of invasion in organotypic thymomas.
authors.affiliation: Department of Pathology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: W I
authors.initials: WI
authors.lastname: Yang
authors.forename: K M
authors.initials: KM
authors.lastname: Yang
authors.forename: S W
authors.initials: SW
authors.lastname: Hong
authors.forename: K D
authors.initials: KD
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015820:Cadherins / Q000032:analysis* / Q000276:immunology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D013945:Thymoma / Q000737:chemistry* / Q000145:classification / Q000473:pathology; D013953:Thymus Neoplasms / Q000737:chemistry* / Q000145:classification / Q000473:pathology
chemical_list: D015820:Cadherins