title: Asian Versus Non-Asian Outcomes in Nasopharyngeal Carcinoma: A North American Population-based Analysis.
abstract: The effect of ethnicity on nasopharyngeal cancer (NPC) outcomes is unclear. This retrospective analysis examines survival and the impact of concurrent chemoradiation (chemoRT) among Asian and non-Asian patients.
  
  
  
  Subjects included 380 consecutive patients with NPC treated at a Canadian institution from 2000 to 2009. Five-year Kaplan-Meier progression-free survival (PFS), disease-specific survival (DSS), and overall survival (OS) were compared between Asian (n=279) and non-Asian (n=101) subjects. Multivariable analysis was performed using Cox regression modeling. Two-variable interaction terms with concurrent chemoRT were used to examine whether concurrent chemoRT conferred different effects among subgroups.
  
  
  
  Asian subjects presented with earlier stage (P=0.005), were younger, had better performance status, and were less likely smokers (all P<0.001). Survival among Asian versus non-Asian subjects with stage I/II NPC were: PFS 68% versus 59% (P=0.04), DSS 87% versus 77% (P=0.08), and OS 84% versus 74% (P=0.003). Corresponding rates with stage III/IVA/IVB disease were PFS 49% versus 42% (P=0.12), DSS 72% versus 46% (P=0.001), and OS 70% versus 44% (P<0.001). On multivariable analysis, Asian ethnicity, age below 65 years, ECOG performance status 0-1, early stage, staging MRI use, and concurrent chemoRT were associated with improved DSS and OS (P<0.05). On testing interactions with concurrent chemoRT, Asian versus non-Asian ethnicity was significant (hazard ratio 3.9), suggesting that concurrent chemoRT conferred more benefit among non-Asian compared with Asian subjects.
  
  
  
  In this population-based study, Asian ethnicity was associated with improved DSS and OS. Concurrent chemoRT conferred more benefit among non-Asian compared with Asian subjects.
authors.affiliation: *Departments of Radiation Oncology ‡Medical Oncology ¶Population Oncology-Surveillance and Outcomes, British Columbia Cancer Agency §Department of Medicine †Department of Surgery, University of British Columbia, Vancouver, BC, Canada ∥Department of Statistics.
authors.forename: Sarah N
authors.initials: SN
authors.lastname: Hamilton
authors.forename: Cheryl
authors.initials: C
authors.lastname: Ho
authors.forename: Janessa
authors.initials: J
authors.lastname: Laskin
authors.forename: Yongliang
authors.initials: Y
authors.lastname: Zhai
authors.forename: Paul
authors.initials: P
authors.lastname: Mak
authors.forename: Jonn
authors.initials: J
authors.lastname: Wu
mesh_terms: D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D044466:Asian People / Q000706:statistics & numerical data*; D001955:British Columbia; D002277:Carcinoma / Q000208:ethnology* / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D059248:Chemoradiotherapy / Q000379:methods; D015331:Cohort Studies; D003131:Combined Modality Therapy; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000208:ethnology* / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D009361:Neoplasm Invasiveness / Q000473:pathology; D009367:Neoplasm Staging; D011379:Prognosis; D016016:Proportional Hazards Models; D020266:Radiotherapy, Conformal / Q000379:methods; D012189:Retrospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome; D044465:White People / Q000706:statistics & numerical data*