CD23 expression in mediastinal large B-cell lymphomas

Histopathology. 2004 Dec;45(6):619-24. doi: 10.1111/j.1365-2559.2004.01969.x.


Aims: Mediastinal large B-cell lymphoma (MLBCL) is a subtype of diffuse large B-cell lymphoma (DLBCL) in the WHO classification with peculiar features, such as female prevalence, young patient age and bulky presentation. It shows a B-cell phenotype with variable expression of surface immunoglobulin, negative CD21 and CD10 and positive CD30 in a large number of cases. An origin from activated thymic B cells has been suggested in several studies. A subpopulation of large, dendritic cells (asteroid cells) strongly expressing CD23 has been identified amongst thymic B cells and these could represent the normal cellular counterpart for this type of primary mediastinal large cell lymphoma.

Methods and results: To explore this possibility, we immunostained 24 cases of primary mediastinal lymphomas and 100 cases of non-mediastinal, nodal and extranodal, DLBCLs for CD23 in routinely processed paraffin-embedded tissues.

Conclusions: Our results show that a vast majority (70%) of mediastinal lymphomas strongly express CD23 whilst the same antigen is expressed in only 15% of non-mediastinal nodal DLBCLs and 9% of non-mediastinal extranodal DLBCLs. These results support the hypothesis that most cases of MLBCL arise from activated dendritic thymic B cells. We also suggest that CD23 should be included in the panel of antibodies currently used to characterize this subtype of DLBCL.

Publication types

  • Comparative Study

MeSH terms

  • Adolescent
  • Adult
  • Antigens, CD20 / analysis
  • DNA-Binding Proteins / analysis
  • Diagnosis, Differential
  • Female
  • Humans
  • Immunohistochemistry
  • Ki-1 Antigen / analysis
  • Lymphoma, B-Cell / metabolism
  • Lymphoma, B-Cell / pathology*
  • Lymphoma, Large B-Cell, Diffuse / metabolism
  • Lymphoma, Large B-Cell, Diffuse / pathology*
  • Male
  • Mediastinal Neoplasms / metabolism
  • Mediastinal Neoplasms / pathology*
  • Middle Aged
  • Proto-Oncogene Proteins / analysis
  • Proto-Oncogene Proteins c-bcl-2 / analysis
  • Proto-Oncogene Proteins c-bcl-6
  • Receptors, IgE / biosynthesis*
  • Transcription Factors / analysis


  • Antigens, CD20
  • DNA-Binding Proteins
  • Ki-1 Antigen
  • Proto-Oncogene Proteins
  • Proto-Oncogene Proteins c-bcl-2
  • Proto-Oncogene Proteins c-bcl-6
  • Receptors, IgE
  • Transcription Factors