title: Plasma Epstein-Barr viral DNA complements TNM classification of nasopharyngeal carcinoma in the era of intensity-modulated radiotherapy.
abstract: BACKGROUND
  The objective of this study is to verify the prognostic value of pretreatment plasma Epstein-Barr viral deoxyribonucleic acid (pEBV DNA) levels in nasopharyngeal carcinoma (NPC) patients to complement TNM classification based on the application of the intensity-modulated radiotherapy (IMRT) technique.
  
  
  METHODS
  In total, 1467 patients staged at I-IVa-b (M0) and treated with IMRT were retrospectively analyzed at our cancer center from January 2007 to December 2010. Patient survival among different stages and EBV DNA levels were compared.
  
  
  RESULTS
  Outcome analyses of different stages and EBV DNA levels revealed that patients in stages II-III with low EBV DNA levels had similar survival as that of patients in stages IVa-b with low EBV DNA (5-yr overall survival (OS), 94.7% vs. 92.9% (P = 0.141), progression failure-free survival (PFS), 87.2% vs. 89.0% (P = 0.685), distant metastasis failure-free survival (DMFS), 93.5% vs. 92.4% (P = 0.394) and locoregional failure-free survival (LRFS), 93.8% vs. 96.3% (P = 0.523)). Conversely, patients in stages II-III with high EBV DNA had better survival than patients in stages IVa-b with high EBV DNA (5-yr OS, 82.7% vs. 71.7% (P = 0.001), PFS, 70.7% vs. 66.2% (P = 0.047), DMFS, 79.6% vs. 74.8% (P = 0.066) and LRFS, 89.3% vs. 87.6% (P = 0.425)) but poorer survival than patients in stages IVa-b with low EBV DNA (5-yr OS, 82.7% vs. 92.9% (P = 0.025), PFS, 70.7% vs. 89.0, (P < 0.001), DMFS, 79.6% vs. 92.4%, (P = 0.001), LRFS, 89.3% vs. 96.3%, (P = 0.022)).
  
  
  CONCLUSIONS
  pEBV DNA is a strong prognostic factor for patients with NPC when complemented with TNM staging in the era of IMRT application.
authors.affiliation: Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, P. R. China.|Department of Nasopharyngeal Carcinoma, Sun Yat-Sen University Cancer Center, Guangzhou, P. R. China.
authors.forename: Lu
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, P. R. China.|Department of Nasopharyngeal Carcinoma, Sun Yat-Sen University Cancer Center, Guangzhou, P. R. China.
authors.forename: Lin-Quan
authors.initials: LQ
authors.lastname: Tang
authors.affiliation: Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, P. R. China.|Department of Nasopharyngeal Carcinoma, Sun Yat-Sen University Cancer Center, Guangzhou, P. R. China.
authors.forename: Qiu-Yan
authors.initials: QY
authors.lastname: Chen
authors.affiliation: Department of Radiotherapy, Hunan Cancer Hospital, Changsha, P. R. China.|Department of Radiotherapy, The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, P. R. China.|Key Laboratory of Translational Radiation Oncology, Changsha, P. R. China.
authors.forename: Huai
authors.initials: H
authors.lastname: Liu
authors.affiliation: Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, P. R. China.|Department of Nasopharyngeal Carcinoma, Sun Yat-Sen University Cancer Center, Guangzhou, P. R. China.
authors.forename: Shan-Shan
authors.initials: SS
authors.lastname: Guo
authors.affiliation: Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, P. R. China.|Department of Nasopharyngeal Carcinoma, Sun Yat-Sen University Cancer Center, Guangzhou, P. R. China.
authors.forename: Li-Ting
authors.initials: LT
authors.lastname: Liu
authors.affiliation: Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, P. R. China.|Department of Nasopharyngeal Carcinoma, Sun Yat-Sen University Cancer Center, Guangzhou, P. R. China.
authors.forename: Ling
authors.initials: L
authors.lastname: Guo
authors.affiliation: Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, P. R. China.|Department of Nasopharyngeal Carcinoma, Sun Yat-Sen University Cancer Center, Guangzhou, P. R. China.
authors.forename: Hao-Yuan
authors.initials: HY
authors.lastname: Mo
authors.affiliation: Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, P. R. China.|Department of Nasopharyngeal Carcinoma, Sun Yat-Sen University Cancer Center, Guangzhou, P. R. China.
authors.forename: Chong
authors.initials: C
authors.lastname: Zhao
authors.affiliation: Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, P. R. China.|Department of Nasopharyngeal Carcinoma, Sun Yat-Sen University Cancer Center, Guangzhou, P. R. China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Guo
authors.affiliation: Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, P. R. China.|Department of Nasopharyngeal Carcinoma, Sun Yat-Sen University Cancer Center, Guangzhou, P. R. China.
authors.forename: Ka-Jia
authors.initials: KJ
authors.lastname: Cao
authors.affiliation: Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, P. R. China.|Department of Nasopharyngeal Carcinoma, Sun Yat-Sen University Cancer Center, Guangzhou, P. R. China.
authors.forename: Chao-Nan
authors.initials: CN
authors.lastname: Qian
authors.affiliation: Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, P. R. China.
authors.forename: Mu-Sheng
authors.initials: MS
authors.lastname: Zeng
authors.affiliation: Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, P. R. China.|Department of Molecular Diagnostics, Sun Yat-Sen University Cancer Center, Guangzhou, P. R. China.
authors.forename: Jian-Yong
authors.initials: JY
authors.lastname: Shao
authors.affiliation: Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, P. R. China.|Department of Radiation Oncology, Sun Yat-Sen University Cancer Center, Guangzhou, P. R. China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, P. R. China.|Department of Radiation Oncology, Sun Yat-Sen University Cancer Center, Guangzhou, P. R. China.
authors.forename: Jun
authors.initials: J
authors.lastname: Ma
authors.affiliation: Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, P. R. China.|GCP Center, Sun Yat-Sen University Cancer Center, Guangzhou, P. R. China.
authors.forename: Ming-Huang
authors.initials: MH
authors.lastname: Hong
authors.affiliation: Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, P. R. China.|Department of Nasopharyngeal Carcinoma, Sun Yat-Sen University Cancer Center, Guangzhou, P. R. China.
authors.forename: Hai-Qiang
authors.initials: HQ
authors.lastname: Mai
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma; D002648:Child; D015331:Cohort Studies; D004279:DNA, Viral / Q000097:blood* / Q000235:genetics; D020031:Epstein-Barr Virus Infections / Q000097:blood* / Q000821:virology; D005260:Female; D004854:Herpesvirus 4, Human / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000097:blood / Q000473:pathology / Q000532:radiotherapy* / Q000821:virology*; D009367:Neoplasm Staging; D011379:Prognosis; D050397:Radiotherapy, Intensity-Modulated; D012189:Retrospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D004279:DNA, Viral
keywords: Epstein-Barr viral DNA; TNM staging; intensity-modulated radiotherapy; nasopharyngeal carcinoma; prognosis