title: Light-chain-restricted germinal centres in reactive lymphadenitis: report of eight cases.
abstract: OBJECTIVE
  Light-chain-restricted germinal centres are generally associated with the existence of a neoplastic lymphoproliferative disorder. The aim was to present a series of cases with persistent lymph node enlargement that featured some germinal centres showing light chain immunoglobulin restriction.
  
  
  RESULTS
  A series of six reactive lymphadenitis and two Castleman's disease cases was analysed by immunohistochemistry, IgH-polymerase chain reaction (PCR) and microdissected PCR. In all cases some germinal centres contained a population of plasma cells and plasmacytoid germinal centre cells showing light chain immunoglobulin restriction. In three cases the monotypic cells also showed distinct Bcl-2 expression. Two of the cases showed a predominant IgH rearrangement on a florid polyclonal background and one had an IgH monoclonal rearrangement, as revealed by PCR. Microdissected germinal centre PCR revealed a dominant repeated band in one of three cases and in another case a non-repeated clonal peak was observed. One of the patients developed a follicular lymphoma, which became evident from a subsequent biopsy.
  
  
  CONCLUSIONS
  These findings may be a manifestation of an underlying disorder in the regulation of the immune response, or an exaggeration of the germinal centre oligoclonal nature. This should be taken into account in the differential diagnosis of follicular hyperplasia.
authors.affiliation: Lymphoma Group, Molecular Pathology Programme, Spanish National Cancer Centre (CNIO), Madrid, Spain. tnamcha@yahoo.es
authors.forename: S H
authors.initials: SH
authors.lastname: Nam-Cha
authors.forename: B
authors.initials: B
authors.lastname: San-Millán
authors.forename: M
authors.initials: M
authors.lastname: Mollejo
authors.forename: M
authors.initials: M
authors.lastname: García-Cosio
authors.forename: G
authors.initials: G
authors.lastname: Garijo
authors.forename: M
authors.initials: M
authors.lastname: Gomez
authors.forename: R A
authors.initials: RA
authors.lastname: Warnke
authors.forename: E S
authors.initials: ES
authors.lastname: Jaffe
authors.forename: M A
authors.initials: MA
authors.lastname: Piris
mesh_terms: D000328:Adult; D000368:Aged; D005871:Castleman Disease / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D005260:Female; D015321:Gene Rearrangement; D005803:Genes, Immunoglobulin / Q000235:genetics; D019254:Genes, bcl-2 / Q000235:genetics; D018858:Germinal Center / Q000276:immunology* / Q000473:pathology; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000235:genetics; D007147:Immunoglobulin Light Chains / Q000235:genetics / Q000276:immunology*; D008199:Lymphadenitis / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D010950:Plasma Cells / Q000276:immunology / Q000473:pathology; D016133:Polymerase Chain Reaction; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000276:immunology
chemical_list: D007143:Immunoglobulin Heavy Chains; D007147:Immunoglobulin Light Chains; D019253:Proto-Oncogene Proteins c-bcl-2