title: Evidence for local immunosuppression and demonstration of c-myc amplification in pyothorax-associated lymphoma.
abstract: OBJECTIVE
  Pyothorax-associated lymphoma (PAL) develops in the pleural cavity of patients with a long history of pyothorax. Epstein-Barr virus (EBV) is also involved in PAL, similar to lymphomas in immunodeficient patients. Here we examined T-lymphocyte subsets as well as c-myc and REL gene amplification in PAL tissues.
  
  
  RESULTS
  We determined the number and distribution of CD4+ and CD8+ T-lymphocytes, to evaluate T-cells in the host immune reaction in seven cases of PAL. As controls, we also studied 10 cases of extranodal diffuse large B-cell lymphoma (DLBL) and 10 cases of nodal DLBL. Chromosomal imbalances in PAL were determined by using comparative genomic hybridization (CGH) analysis. The mean numbers of CD4+ and CD8+ and their ratio were significantly lower in PAL than in nodal DLBL. CGH analysis of PAL showed amplification of the 8q24 chromosomal region. In addition, c-myc amplification was found in four cases of PAL by Southern blot analysis.
  
  
  CONCLUSIONS
  Our results suggest that the development of PAL may involve a local immunosuppressive environment and that amplification of c-myc might promote tumour progression, as has been described in the development of Burkitt's lymphoma.
authors.affiliation: Department of Pathology, School of Medicine, Fukuoka University, Nanakuma 7-45-1, Jonanku, Fukuoka 814-0180, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Yamato
authors.forename: K
authors.initials: K
authors.lastname: Ohshima
authors.forename: J
authors.initials: J
authors.lastname: Suzumiya
authors.forename: M
authors.initials: M
authors.lastname: Kikuchi
mesh_terms: D000368:Aged; D015139:Blotting, Southern; D016516:CD4-CD8 Ratio; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology; D002869:Chromosome Aberrations / Q000235:genetics; D004247:DNA / Q000235:genetics; D016724:Empyema, Pleural / Q000150:complications*; D020031:Epstein-Barr Virus Infections / Q000473:pathology / Q000821:virology; D005260:Female; D005784:Gene Amplification; D016259:Genes, myc / Q000235:genetics*; D004854:Herpesvirus 4, Human / Q000235:genetics; D006801:Humans; D016130:Immunophenotyping; D007165:Immunosuppression Therapy; D017403:In Situ Hybridization; D018655:Lymphocyte Count; D008223:Lymphoma / Q000209:etiology / Q000235:genetics / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009693:Nucleic Acid Hybridization
chemical_list: D004247:DNA