title: Increased risk of ischemic stroke in young nasopharyngeal carcinoma patients.
abstract: OBJECTIVE
  Radiation/chemoradiotherapy-induced carotid stenosis and cerebrovascular events in patients with nasopharyngeal carcinoma (NPC) can cause severe disability and even death. This study aimed to estimate the risk of ischemic stroke in this patient population over more than 10 years of follow-up.
  
  
  METHODS
  The study cohorts consisted of all patients hospitalized with a principal diagnosis of NPC (n=1094), whereas patients hospitalized for an appendectomy during 1997 and 1998 (n=4376) acted as the control group and surrogate for the general population. Cox proportional hazard model was performed as a means of comparing the stroke-free survival rate between the two cohorts after adjusting for possible confounding and risk factors.
  
  
  RESULTS
  Of the 292 patients with ischemic strokes, 62 (5.7%) were from the NPC cohort and 230 (5.3%) were from the control group. NPC patients ages 35-54 had a 1.66 times (95% CI, 1.16-2.86; p=0.009) higher risk of ischemic stroke after adjusting for patient characteristics, comorbidities, geographic region, urbanization level of residence, and socioeconomic status. There was no statistical difference in ischemic stroke risk between the NPC patients and appendectomy patients ages 55-64 years (hazard ratio=0.87; 95% CI, 0.56-1.33; p=0.524) after adjusting for other factors.
  
  
  CONCLUSIONS
  Young NPC patients carry a higher risk for ischemic stroke than the general population. Besides regular examinations of carotid duplex, different irradiation strategies or using new technique of radiotherapy, such as intensity modulated radiation therapy or volumetric modulated arc therapy, should be considered in young NPC patients.
authors.affiliation: Community Medicine Research Center and Institute of Public Health, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Ching-Chih
authors.initials: CC
authors.lastname: Lee
authors.forename: Yu-Chieh
authors.initials: YC
authors.lastname: Su
authors.forename: Hsu-Chueh
authors.initials: HC
authors.lastname: Ho
authors.forename: Shih-Kai
authors.initials: SK
authors.lastname: Hung
authors.forename: Moon-Sing
authors.initials: MS
authors.lastname: Lee
authors.forename: Wen-Yen
authors.initials: WY
authors.lastname: Chiou
authors.forename: Pesus
authors.initials: P
authors.lastname: Chou
authors.forename: Yung-Sung
authors.initials: YS
authors.lastname: Huang
mesh_terms: D000328:Adult; D000367:Age Factors; D001062:Appendectomy / Q000009:adverse effects / Q000401:mortality; D002277:Carcinoma; D016893:Carotid Stenosis / Q000209:etiology; D016022:Case-Control Studies; D059248:Chemoradiotherapy / Q000009:adverse effects; D015331:Cohort Studies; D015986:Confounding Factors, Epidemiologic; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000628:therapy*; D016016:Proportional Hazards Models; D011878:Radiotherapy / Q000009:adverse effects; D012306:Risk; D020521:Stroke / Q000209:etiology* / Q000401:mortality; D013624:Taiwan