title: En bloc resection concept for endoscopic endonasal nasopharyngectomy: surgical anatomy and outcome.
abstract: BACKGROUND
  Nasopharyngeal carcinoma (NPC) patients have a 19%-56% locoregional recurrence rate after primary therapy. For those recurrent NPC (rNPC) patients, re-irradiation may cause some complications. In recent years, endoscopic endonasal nasopharyngectomy (EEN) has become a surgical option for rNPC patients. Here we introduce the concept of en bloc excision (EBE) technique for EEN, including the surgical technique and clinical outcomes.
  
  
  METHODS
  A retrospective study was conducted covering September 2009 to May 2013, involving the collection of locoregional rNPC cases from two institutions (Kuang-Tien General Hospital (KTGH) in Taiwan and National University Health System (NUHS) in Singapore). These patients failed prior therapy and then underwent EEN. We reported the 2-year overall survival rate, the 2-year disease-free survival rate, and related complications.
  
  
  RESULTS
  Nine patients (five from KTGH and four from NUHS) completed this study, with five, two, and two patients of recurrence tumors (rT1), rT2, and rT3, respectively. The mean age was 46.4 years (range 32-63); the mean follow-up period was 24.9 months (range 10-45). The 2-year survival rate and the 2-year disease-free rate were 100% and 80%, respectively, in five patients. No significant complications or cases of mortality occurred.
  
  
  CONCLUSIONS
  The EBE concept of EEN is suitable for early rT1 and has relatively encouraging short-term outcomes. In selected rT2, careful EBE can be performed by expanding the surgical field. A clear view of the internal carotid artery-related anatomy is indispensable. In the future, more series may be needed to determine the role of EEN in rNPC patients.
authors.affiliation: Department of Otolaryngology, Kuang-Tien General Hospital, Taichung, Taiwan, China.
authors.forename: Ning-i
authors.initials: NI
authors.lastname: Hsu
authors.affiliation: Department of Otolaryngology, Kuang-Tien General Hospital, Taichung, Taiwan, China; Department of Biotechnology, Hung-Kuang University, Taichung, Taiwan, China.
authors.forename: Ping-hung
authors.initials: PH
authors.lastname: Shen
authors.affiliation: Department of Otolaryngology Head and Neck Surgery, National University Hospital, Singapore.
authors.forename: Siew-shuen
authors.initials: SS
authors.lastname: Chao
authors.affiliation: Department of Otolaryngology Head and Neck Surgery, National University Hospital, Singapore.
authors.forename: Yew-kwang
authors.initials: YK
authors.lastname: Ong
authors.affiliation: Department of Neurosurgery, Chung-Shan Medical University Hospital, Taichung, Taiwan, China; School of Medicine, Chung-Shan Medical University, Taichung, Taiwan, China. Email: hkli@ms28.hinet.net; cshy1350@csh.org.tw.
authors.forename: Cho-shun
authors.initials: CS
authors.lastname: Li
mesh_terms: D000328:Adult; D002277:Carcinoma; D004724:Endoscopy / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000601:surgery*; D012189:Retrospective Studies; D016896:Treatment Outcome