title: Prognostic value of prepontine cistern invasion in nasopharyngeal carcinoma treated by intensity-modulated radiotherapy.
abstract: OBJECTIVE
  To investigate the prognostic value of prepontine cistern invasion (PPCI) in nasopharyngeal carcinoma (NPC) patients treated with intensity-modulated radiotherapy (IMRT).
  
  
  METHODS
  Five hundred and four non-disseminated NPC patients who underwent magnetic resonance imaging examination before radical IMRT between November 2000 and December 2008 were retrospectively reviewed. The diagnostic criteria for PPCI were tumor invasion through the posterior cortex of clivus and extension into the prepontine cistern.
  
  
  RESULTS
  The median follow-up of the patients in this study was 63.5 months. PPCI was found in 44 patients (25% of T4 patients). The 5-year progression-free survival (PFS), local control (LC), distant metastasis-free survival (DMFS), and overall survival (OS) of all patients, with and without PPCI, were 44.3% and 70.5% (p<0.001), 84.4% and 89.1% (p=0.376), 66.6% and 87.3% (p<0.001), and 59.6% and 80.2% (p<0.001), respectively. In T4 patients with PPCI and without PPCI, the 5-year PFS, LC, DMFS, and OS were 44.3% and 62.5% (p=0.023), 84.4% and 84.9% (p=0.946), 66.6% and 83.1% (p=0.022), and 59.6% and 71.0% (p=0.045), respectively. Using multivariate analysis, PPCI was found to be an independent poor prognostic factor for PFS (HR=1.816; p=0.007), DMFS (HR=1.928; p=0.045), and OS (HR=1.798; p=0.016).
  
  
  CONCLUSIONS
  Prepontine cistern invasion was an independent prognostic factor for poor DMFS and OS but not LC in NPC patients treated with IMRT, even within T4 patients.
authors.affiliation: Department of Radiation Oncology, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan.
authors.forename: Tsung-Min
authors.initials: TM
authors.lastname: Hung
authors.affiliation: Department of Diagnostic Radiology, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan.
authors.forename: Chien-Cheng
authors.initials: CC
authors.lastname: Chen
authors.affiliation: Department of Radiation Oncology, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan.
authors.forename: Chien-Yu
authors.initials: CY
authors.lastname: Lin
authors.affiliation: Department of Diagnostic Radiology, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan.
authors.forename: Shu-Hang
authors.initials: SH
authors.lastname: Ng
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan.
authors.forename: Chung-Jan
authors.initials: CJ
authors.lastname: Kang
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan.
authors.forename: Shiang-Fu
authors.initials: SF
authors.lastname: Huang
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan.
authors.forename: Chun-Ta
authors.initials: CT
authors.lastname: Liao
authors.affiliation: Department of Radiation Oncology, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan.
authors.forename: Kang-Hsing
authors.initials: KH
authors.lastname: Fan
authors.affiliation: Division of Hematology/Oncology, Department of Internal Medicine, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan.
authors.forename: Hung-Ming
authors.initials: HM
authors.lastname: Wang
authors.affiliation: Department of Radiation Oncology, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan. Electronic address: cgmhnog@gmail.com.
authors.forename: Joseph Tung-Chieh
authors.initials: JT
authors.lastname: Chang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000175:diagnosis / Q000473:pathology* / Q000532:radiotherapy; D011379:Prognosis; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods; D012189:Retrospective Studies; D019292:Skull Base Neoplasms / Q000175:diagnosis / Q000473:pathology*; D016896:Treatment Outcome; D055815:Young Adult
keywords: Distant metastasis; Head and neck cancer; Intensity-modulated radiotherapy; Intracranial extension; Nasopharyngeal carcinoma; Prepontine cistern invasion; Prognosis