title: Dissolution of the lymphoid follicle is a feature of the HHV8+ variant of plasma cell Castleman's disease.
abstract: The plasma cell variant of Castleman's disease (PCD) may occur in a variety of clinical settings. One recently delineated type of PCD is caused by human herpesvirus 8 (HHV8) infection. Lymph nodes from 25 patients with PCD, including six HHV8+ and 19 HHV8- cases, were studied. Three patients with HHV8+ PCD were also infected with human immunodeficiency virus-1. Features common to all cases were interfollicular plasmacytosis and variably hyperplastic and regressed follicle germinal centers. Features associated only with HHV8+ PCD included follicle dissolution resulting from blurring of the mantle zone boundary (p = 0.0001), presence of atypical plasma cells and immunoblasts within these areas (p = 0.0006), and more prominent interfollicular vascular proliferation than in HHV8- PCD. HHV8+ cells were predominantly immunoblasts and small lymphocytes that were highly enriched in the mantle zones of altered follicles. These areas showed a predominance of plasmacytoid forms expressing lambda light chain in four of six cases. The extrafollicular fibroblastic network surrounding altered germinal centers demonstrated marked upregulation of low-affinity nerve growth factor receptor in five of five HHV8+ cases but in only two of 10 HHV8- cases. We conclude that HHV8+ PCD is distinctive histologically because of the accumulation of infected lymphocytes in the mantle zone leading to progressive dissolution of the germinal center and altered regulation of the surrounding stroma.
authors.affiliation: Department of Hematopathology, University of Texas--M.D. Anderson Cancer Center, Houston, 77030, USA.
authors.forename: Hesham M
authors.initials: HM
authors.lastname: Amin
authors.forename: L Jeffrey
authors.initials: LJ
authors.lastname: Medeiros
authors.forename: John T
authors.initials: JT
authors.lastname: Manning
authors.forename: Dan
authors.initials: D
authors.lastname: Jones
mesh_terms: D017088:AIDS-Related Opportunistic Infections / Q000150:complications / Q000473:pathology; D005871:Castleman Disease / Q000473:pathology* / Q000821:virology; D004279:DNA, Viral / Q000032:analysis; D018858:Germinal Center / Q000473:pathology*; D015497:HIV-1 / Q000302:isolation & purification; D006566:Herpesviridae Infections / Q000150:complications / Q000473:pathology*; D019288:Herpesvirus 8, Human / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D006801:Humans; D007124:Immunoenzyme Techniques; D009687:Nuclear Proteins / Q000032:analysis / Q000276:immunology; D010750:Phosphoproteins / Q000032:analysis / Q000276:immunology; D010950:Plasma Cells / Q000473:pathology*; D016133:Polymerase Chain Reaction; D012514:Sarcoma, Kaposi / Q000150:complications / Q000473:pathology
chemical_list: D004279:DNA, Viral; D009687:Nuclear Proteins; D010750:Phosphoproteins; C118485:latent nuclear antigen (LNA)