title: [Correlation between the kinetics of plasma EBV DNA levels and clinical response during treatment in patients with nasopharyngeal carcinoma].
abstract: OBJECTIVE
  Nasopharyngeal carcinoma(NPC) is an EB virus (EBV) related cancer. Recently, it was reported that EBV DNA can be detected in NPC patients' plasma or serum. This study was designed to investigate the correlation between the kinetics of plasma EBV DNA levels and clinical response during concomitant chemo-radiotherapy in the locally advanced nasopharyngeal carcinoma patients.
  
  
  METHODS
  Blood samples from 20 patients were collected weekly during chemo-radiotherapy(7 times, in total). The first blood sample was collected before treatment. The content of EBV DNA in the samples were detected by using fluorescent quantitative PCR method in the PE Appliance Biosystems 7700 Sequence Detector.
  
  
  RESULTS
  Before treatment, plasma EBV DNA was detectable in the plasma of 90% (18/20) NPC patients. The median concentration was 150,000(copies/ml). Two patients' plasma EBV DNA could not be detected during the whole course of treatment. Among 18 EBV DNA-positive patients, 3 patients had a continuously high EBV DNA and clinical examination after treatment indicated that they had residual tumors. Seven patients'plasma EBV DNA levels had a rapid decline to be undetectable. Eight patients' plasma EBV DNA levels got a slow decline, but the EBV DNA could not be detected at the end of therapy as well. Clinical examination revealed that all of these 15 patients had complete tumor regression.
  
  
  CONCLUSIONS
  Kinetic analysis of plasma EBV DNA during treatment may be a useful tool to monitor the treatment response in NPC patients. Further investigation is warranted.
authors.affiliation: Department of Medical Oncology, Cancer Center, Sun Yat-sen University, Guangzhou 510060, P. R. China.
authors.forename: Pei-jian
authors.initials: PJ
authors.lastname: Peng
authors.forename: Chong
authors.initials: C
authors.lastname: Zhao
authors.forename: Hai
authors.initials: H
authors.lastname: Liao
authors.forename: Fu-qiang
authors.initials: FQ
authors.lastname: Wang
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
mesh_terms: D000328:Adult; D000970:Antineoplastic Agents / Q000627:therapeutic use; D004279:DNA, Viral / Q000097:blood* / Q000187:drug effects; D020031:Epstein-Barr Virus Infections / Q000097:blood* / Q000150:complications / Q000188:drug therapy; D005260:Female; D004854:Herpesvirus 4, Human / Q000187:drug effects / Q000235:genetics*; D006801:Humans; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000150:complications / Q000188:drug therapy*; D016133:Polymerase Chain Reaction; D013997:Time Factors
chemical_list: D000970:Antineoplastic Agents; D004279:DNA, Viral