title: Circulating Epstein-Barr virus DNA in serum of patients with lymphoepithelioma-like carcinoma of the lung: a potential surrogate marker for monitoring disease.
abstract: OBJECTIVE
  The purpose of this work was to study the sera of patients with lymphoepithelioma-like carcinoma (LELC) of the lung for circulating EBV DNA.
  
  
  METHODS
  Prospectively collected serum samples from five female patients with advanced, inoperable LELC of the lung were measured for free circulating EBV DNA using a quantitative PCR technique. EBV-encoded small RNA (EBER)-1 was assayed in serial serum samples of three of the five patients, either from the start or during the initial phase of chemotherapy/radiotherapy until their terminal event or last follow-up. There was only a single-point sample for analysis in the fourth and fifth patients. Six other patients with LELC of the lung were also retrospectively identified, and their sera were tested for EBER-1 at either the first visit plus the last follow-up visit (n = 2), the first visit only (n = 2), or the last follow-up visit only (n = 2).
  
  
  RESULTS
  Prospectively collected serum samples from five patients and retrospectively collected serum samples from two patients who had clinical disease at initial serum measurement showed detectable levels of EBER-1. Retrospectively collected serum samples from four patients with no clinical disease had negative sera. There is consistent correlation between the clinical response to treatment and subsequent clinical course of LELC and serum EBER-1 levels in the three prospective patients with longitudinal serum monitoring.
  
  
  CONCLUSIONS
  This study shows for the first time that free EBV DNA can be detected in the serum of patients with LELC of the lung and further suggests the feasibility of its use for monitoring response to therapy in advanced cases.
authors.affiliation: Department of Clinical Oncology, Queen Elizabeth Hospital, Hong Kong Special Administrative Region, China. ngankc@ha.org.hk
authors.forename: Roger K C
authors.initials: RK
authors.lastname: Ngan
authors.forename: Timothy T C
authors.initials: TT
authors.lastname: Yip
authors.forename: Wai-Wai
authors.initials: WW
authors.lastname: Cheng
authors.forename: John K C
authors.initials: JK
authors.lastname: Chan
authors.forename: William C S
authors.initials: WC
authors.lastname: Cho
authors.forename: Victor W S
authors.initials: VW
authors.lastname: Ma
authors.forename: Kwong-Kee
authors.initials: KK
authors.lastname: Wan
authors.forename: Siu-Kie
authors.initials: SK
authors.lastname: Au
authors.forename: Chun-Key
authors.initials: CK
authors.lastname: Law
authors.forename: Wai-Hon
authors.initials: WH
authors.lastname: Lau
mesh_terms: D000328:Adult; D000956:Antigens, Viral / Q000276:immunology; D014408:Biomarkers, Tumor / Q000097:blood; D002213:Capsid / Q000276:immunology; D002294:Carcinoma, Squamous Cell / Q000097:blood* / Q000188:drug therapy / Q000532:radiotherapy; D004279:DNA, Viral / Q000097:blood*; D020031:Epstein-Barr Virus Infections / Q000097:blood* / Q000821:virology; D017809:Fatal Outcome; D004854:Herpesvirus 4, Human / Q000235:genetics* / Q000276:immunology; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood; D008175:Lung Neoplasms / Q000097:blood* / Q000188:drug therapy / Q000532:radiotherapy; D008875:Middle Aged; D012367:RNA, Viral / Q000097:blood / Q000187:drug effects / Q000528:radiation effects; D012074:Remission Induction; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000956:Antigens, Viral; D014408:Biomarkers, Tumor; D004279:DNA, Viral; C099537:Epstein-Barr virus encoded RNA 1; D007070:Immunoglobulin A; D012367:RNA, Viral