title: Comparative study on prophylactic irradiation to the whole neck and to the upper neck for patients with neck lymph node-negative nasopharyngeal carcinoma.
abstract: BACKGROUND
  The purpose of this study was to investigate the prophylactic irradiation volume to neck drainage areas for patients with N0 classification nasopharyngeal carcinoma (NPC) treated by intensity-modulated radiotherapy (IMRT).
  
  
  METHODS
  From January 2003 to October 2008, 270 patients with N0 classification (American Joint Committee on Cancer [AJCC] 2002 staging system) NPC who had undergone IMRT were retrospectively analyzed. Among all the patients, 171 patients received prophylactic upper-neck irradiation, and 99 patients received prophylactic whole-neck irradiation.
  
  
  RESULTS
  At a median follow-up of 65.1 months (range, 4-106 months). The 5-year overall survival (OS), nodal recurrence-free survival (NRFS), and distant metastasis-free survival (DMFS) rates of the upper neck group and the whole neck group were 93.6% vs 90.9% (p = .553), 99.4% vs 99.0% (p = .278), and 98.8% vs 94.9% (p = .128), respectively. A total of 3 neck recurrences were found, including 2 from the whole neck group and 1 from the upper neck group. The latter (0.6%) was an out-of-field recurrence.
  
  
  CONCLUSIONS
  Prophylactic irradiation to the upper neck (levels II, III, and VA) may be feasible for patients with neck lymph node-negative NPC.
authors.affiliation: State Key Laboratory Oncology in Southern China, Guangzhou, People's Republic of China; Department of Radiation Oncology, Cancer Center of Sun Yat-Sen University, Guangzhou, People's Republic of China.
authors.forename: Lei
authors.initials: L
authors.lastname: Zeng
authors.forename: Xue-Ming
authors.initials: XM
authors.lastname: Sun
authors.forename: Chun-Yan
authors.initials: CY
authors.lastname: Chen
authors.forename: Fei
authors.initials: F
authors.lastname: Han
authors.forename: Ying
authors.initials: Y
authors.lastname: Huang
authors.forename: Wei-Wei
authors.initials: WW
authors.lastname: Xiao
authors.forename: Shuai
authors.initials: S
authors.lastname: Liu
authors.forename: Yun-Ming
authors.initials: YM
authors.lastname: Tian
authors.forename: Xiao-Wu
authors.initials: XW
authors.lastname: Deng
authors.forename: Tai-Xiang
authors.initials: TX
authors.lastname: Lu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002277:Carcinoma; D015331:Cohort Studies; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008198:Lymph Nodes / Q000473:pathology / Q000528:radiation effects; D015182:Lymphatic Irradiation / Q000379:methods*; D008297:Male; D008875:Middle Aged; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000401:mortality* / Q000473:pathology / Q000532:radiotherapy*; D009333:Neck; D009361:Neoplasm Invasiveness / Q000473:pathology; D009367:Neoplasm Staging; D011322:Primary Prevention / Q000379:methods; D011379:Prognosis; D016016:Proportional Hazards Models; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods*; D012189:Retrospective Studies; D018570:Risk Assessment; D018709:Statistics, Nonparametric; D015996:Survival Rate; D016896:Treatment Outcome; D055815:Young Adult
keywords: elective irradiation; intensity-modulated radiotherapy; nasopharyngeal carcinoma; neck lymph node-negative; retropharyngeal lymph node