title: Long-term clinical outcome in nasopharyngeal carcinoma patients with post-radiation persistently detectable plasma EBV DNA.
abstract: OBJECTIVE
  To investigate the long-term clinical outcome of nasopharyngeal carcinoma (NPC) patients with persistently detectable plasma EBV (pEBV) DNA after curative radiotherapy (RT).
  
  
  RESULTS
  The post-RT pEBV DNA levels were very lower copy number (median 21, interquartile range 8-206 copies/ml). After long-term follow-up, the relapse rate was 64.8%, the median time to progression 20 months, and 5-year overall survival (OS) 49.6%. Thirty-two of 39 (82.1%) patients with high viral load (≥ 100 copies/ ml) developed tumor relapse, whereas 57.0% (49/86) patients with low viral load (< 100 copies/ml) had tumor relapse (P = 0.0065). The 5-year OS rates were 20.5% and 62.9% for patients with viral load ≥ and < 100 copies/ml (median survival, 20 vs. 100 months; P < 0.0001). Patients who received adjuvant chemotherapy (AdjCT) experienced significant reduction in distant failures (66.2% vs. 31.6%; P = 0.0001) but similar locoregional recurrences (P = 0.2337). The 5-year OS rates were 69.4% for patients who received AdjCT compared with 33.2% for those of without AdjCT (median survival, 111 vs. 32 months; P < 0.0001).
  
  
  METHODS
  We screened 931 newly diagnosed NPC patients who finished curative RT and found 125 patients (13.4%) with detectable pEBV DNA one week after RT. The clinical characteristics, treatment modality, subsequent failure patterns and survivals were analyzed.
  
  
  CONCLUSIONS
  NPC patients with persistently detectable pEBV DNA after curative RT have a higher rate of treatment failure and poor survivals. Levels of the post-RT pEBV DNA and administration of AdjCT affect the final outcome significantly.
authors.affiliation: Department of Nursing, Hung Kuang University, Taichung, Taiwan.|Department of Nursing, National Taichung University of Science and Technology, Taichung, Taiwan.
authors.forename: Wen-Yi
authors.initials: WY
authors.lastname: Wang
authors.affiliation: Department of Otorhinolaryngology, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Tian-Yun
authors.initials: TY
authors.lastname: Lin
authors.affiliation: Department of Otorhinolaryngology, Taichung Veterans General Hospital, Taichung, Taiwan.|Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Chih-Wen
authors.initials: CW
authors.lastname: Twu
authors.affiliation: Institute of Population Health Sciences, National Health Research Institutes, Miaoli, Taiwan.|Graduate Institute of Biostatistics, College of Public Health, China Medical University, Taichung, Taiwan.
authors.forename: Hsiao-Hui
authors.initials: HH
authors.lastname: Tsou
authors.affiliation: Department of Radiation Oncology, Taichung Veterans General Hospital, Taichung, Taiwan.
authors.forename: Po-Ju
authors.initials: PJ
authors.lastname: Lin
authors.affiliation: Department of Radiation Oncology, Taichung Veterans General Hospital, Taichung, Taiwan.
authors.forename: Yi-Chun
authors.initials: YC
authors.lastname: Liu
authors.affiliation: Department of Radiation Oncology, Taichung Veterans General Hospital, Taichung, Taiwan.
authors.forename: Jing-Wen
authors.initials: JW
authors.lastname: Huang
authors.affiliation: Department of Radiation Oncology, Taichung Veterans General Hospital, Taichung, Taiwan.
authors.forename: He-Yuan
authors.initials: HY
authors.lastname: Hsieh
authors.affiliation: Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan.|Department of Radiation Oncology, Taichung Veterans General Hospital, Taichung, Taiwan.|Institute of Clinical Medicine,School of Medicine, National Yang Ming University, Taipei, Taiwan.|Department of Medicine, China Medical University, Taichung, Taiwan.
authors.forename: Jin-Ching
authors.initials: JC
authors.lastname: Lin
mesh_terms: D000328:Adult; D002277:Carcinoma / Q000097:blood / Q000532:radiotherapy* / Q000821:virology; D017024:Chemotherapy, Adjuvant; D004279:DNA, Viral / Q000097:blood*; D018450:Disease Progression; D018572:Disease-Free Survival; D020031:Epstein-Barr Virus Infections / Q000097:blood; D005260:Female; D005500:Follow-Up Studies; D004854:Herpesvirus 4, Human; D006801:Humans; D008297:Male; D008875:Middle Aged; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000097:blood / Q000532:radiotherapy* / Q000821:virology; D009364:Neoplasm Recurrence, Local; D011379:Prognosis; D011878:Radiotherapy / Q000379:methods; D012008:Recurrence; D016896:Treatment Outcome; D019562:Viral Load
chemical_list: D004279:DNA, Viral
keywords: nasopharyngeal carcinoma; plasma Epstein-Barr virus DNA; quantitative polymerase chain reaction; radiotherapy