title: Epithelioid cell granulomatous response of Waldeyer's ring among Japanese : a clinicopathological and immunohistochemical study of 16 cases.
abstract: The tonsils are uncommonly affected by granulomatous inflammation. This study attempted to clarify the clinicopathological and immunohistochemical findings and presence or absence of Epstein-Barr virus (EBV) in tonsilar granulomatous inflammation. A total of 537 consecutive specimens from tonsillectomies performed at Dokkyo University School of Medicine between 1999 and March 2012 were reexamined. Using formalin-fixed, paraffin-embedded sections, histological, immunohistochemical, and in situ hybridization (ISH) studies were performed. Epithelioid granulomas (EPGs) were identified in the tonsils in 16 (3.0%) cases. There were 8 males and 8 females, aged 4 to 57 years (mean, 23). In 11 patients, EPGs were located in the germinal center (GC), whereas they were located in the interfollicular area as well as GC in the remaining 5 cases. Three types of EPG have been delineated : (i) poorly demarcated small epithelioid cell granulomas (n = 6) ; (ii) well-demarcated non-caseating sarcoid-like granulomas (n = 5) ; and (iii) EPGs within GC showing suppurations at the center (n = 5). An ISH study demonstrated EBV-encoded small RNA (EBER)(+) cells in 4 lesions. The present study demonstrated that the majority of EPGs were located in the GC and tonsilar EPGs showed histological variation.
authors.affiliation: Department of Anatomic and Diagnostic Pathology, Dokkyo University School of Medicine, Mibu, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Kaneko
authors.forename: Masaru
authors.initials: M
authors.lastname: Kojima
authors.forename: Yoshimasa
authors.initials: Y
authors.lastname: Nakazato
authors.forename: Nobuhide
authors.initials: N
authors.lastname: Masawa
mesh_terms: D000293:Adolescent; D000328:Adult; D044466:Asian People; D002648:Child; D002675:Child, Preschool; D015622:Epithelioid Cells / Q000473:pathology* / Q000821:virology; D020031:Epstein-Barr Virus Infections / Q000473:pathology* / Q000821:virology; D005260:Female; D005404:Fixatives; D005557:Formaldehyde; D018858:Germinal Center / Q000473:pathology* / Q000821:virology; D006099:Granuloma / Q000473:pathology* / Q000821:virology; D004854:Herpesvirus 4, Human; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008297:Male; D008875:Middle Aged; D014066:Palatine Tonsil / Q000473:pathology* / Q000821:virology; D016612:Paraffin Embedding; D012189:Retrospective Studies; D014068:Tonsillectomy
chemical_list: D005404:Fixatives; D005557:Formaldehyde