title: Impact of Epstein-Barr virus in the clinical evolution of patients with classical Hodgkin's lymphoma in Brazil.
abstract: BACKGROUND
  Classical Hodgkin's Lymphoma (cHL) has been frequently associated with Epstein-Barr virus (EBV), which can be found in a latent pattern in Reed-Sternberg (RS) cells. However, the impact of the presence of EBV in RS cells and its prognosis are still controversial. We analysed the presence of EBV in RS cells and its influence in the clinical evolution of patients with cHL treated in two public hospitals in the city of São Paulo, Brazil.
  
  
  METHODS
  We selected 97 patients with cHL from 1994 to 2004. Patients were only included in this study if they had (1) >18 years, (2) negative HIV serology, (3) undergone similar chemotherapy protocols, (4) paraffin blocks available with enough material for systematic review and histological reclassification and for detection of EBV in RS cells by in situ hybridization and immunohistochemistry and (5) clinical, epidemiological and laboratorial parameters available after a thorough chart review.
  
  
  RESULTS
  EBV was identified in 52.5% of the cases. Mixed cellularity (MC) subtype was more common in EBV-related tumours (25.5%) (p=0.005). There was no difference on age, gender, stage and the presence of B symptoms between the two groups. The presence of EBV did not influence event free survival (EFS) (p=0.38) or overall survival (OS) (p=0.80) with a median follow-up of 80 months.
  
  
  CONCLUSIONS
  We demonstrate that the prevalence of EBV-related cHL in this Brazilian population is 52.5% and, that, the presence of EBV does not change the clinical evolution and OS of patients treated with similar chemotherapy protocols.
authors.affiliation: Federal University of São Paulo (UNIFESP), Hematology and Transfusion Service, São Paulo, SP, Brazil.
authors.forename: Eni M
authors.initials: EM
authors.lastname: Souza
authors.forename: Otávio C G
authors.initials: OC
authors.lastname: Baiocchi
authors.forename: Maria A
authors.initials: MA
authors.lastname: Zanichelli
authors.forename: Antonio C
authors.initials: AC
authors.lastname: Alves
authors.forename: Marianne G
authors.initials: MG
authors.lastname: Assis
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Eiras
authors.forename: Cristine
authors.initials: C
authors.lastname: Dobo
authors.forename: José S R
authors.initials: JS
authors.lastname: Oliveira
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001938:Brazil; D018572:Disease-Free Survival; D020031:Epstein-Barr Virus Infections / Q000473:pathology* / Q000821:virology; D005260:Female; D004854:Herpesvirus 4, Human / Q000235:genetics / Q000302:isolation & purification*; D006689:Hodgkin Disease / Q000473:pathology / Q000821:virology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D016019:Survival Analysis; D055815:Young Adult