title: Epstein-Barr Virus in Nasopharyngeal Carcinoma of Guatemalan and Brazilian Patients.
abstract: BACKGROUND
  Nasopharyngeal carcinoma (NPC) is highly associated with Epstein-Barr virus (EBV), particularly the undifferentiated nonkeratinizing subtype. Prevalence of EBV in NPC in countries such as Guatemala and Brazil has not been studied.
  
  
  METHODS
  We analyzed 19 cases of NPC, 11 from Guatemala and 8 from Brazil, for the presence of EBV by in situ hybridization and immunohistochemistry. Additionally, 19 hyperplastic adenoids from children were analyzed for EBV by in situ hybridization, 12 from Guatemala and 7 from Brazil.
  
  
  RESULTS
  All the NPC cases from Guatemala and 5 from Brazil were of the undifferentiated nonkeratinizing type. EBV-negative cases comprised 2 keratinizing NPC and 1 differentiated nonkeratinizing NPC. All undifferentiated nonkeratinizing NPC from both samples showed intense positivity for EBER, while LMP-1 only focally and scarcely expressed. EBER was positive in 75% and 43% of the adenoids from Guatemala and Brazil, respectively.
  
  
  CONCLUSIONS
  All undifferentiated nonkeratinizing NPC irrespective of origin from Guatemala or Brazil were highly associated with EBV.
authors.affiliation: 1 University of Campinas (UNICAMP), Piracicaba, Brazil.
authors.forename: Alicia
authors.initials: A
authors.lastname: Rumayor Piña
authors.affiliation: 1 University of Campinas (UNICAMP), Piracicaba, Brazil.
authors.forename: Harim Tavares
authors.initials: HT
authors.lastname: Dos Santos
authors.affiliation: 2 Centro Clínico de Cabeza y Cuello/Hospital Herrera Llerandi, Ciudad de Guatemala, Guatemala.
authors.forename: Roman
authors.initials: R
authors.lastname: Carlos
authors.affiliation: 3 Department of Pathology, Medical Sciences Faculty, University of Campinas (UNICAMP), Campinas, Brazil.
authors.forename: Albina
authors.initials: A
authors.lastname: Altemani
authors.affiliation: 1 University of Campinas (UNICAMP), Piracicaba, Brazil.
authors.forename: Oslei Paes
authors.initials: OP
authors.lastname: de Almeida
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001938:Brazil / Q000453:epidemiology; D002277:Carcinoma / Q000821:virology*; D020031:Epstein-Barr Virus Infections / Q000150:complications / Q000453:epidemiology*; D005260:Female; D006166:Guatemala / Q000453:epidemiology; D004854:Herpesvirus 4, Human; D006801:Humans; D008297:Male; D008875:Middle Aged; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000821:virology*; D055815:Young Adult
keywords: Epstein-Barr virus; adenoid; carcinoma; in situ hybridization; nasopharynx