title: Long-term effects on carotid intima-media thickness after radiotherapy in patients with nasopharyngeal carcinoma.
abstract: BACKGROUND
  Vascular abnormalities are the predominant histologic changes associated with radiation in nasopharyngeal carcinoma (NPC). This study examined if the duration after radiotherapy correlates with the progression of carotid intima-media thickness (IMT) and investigated its relationship with inflammatory markers.
  
  
  METHODS
  One hundred and five NPC patients post-radiotherapy for more than one year and 25 healthy control subjects were examined by B-mode ultrasound for IMT measurement at the far wall of the common carotid artery (CCA). Surrogate markers including lipid profile, HbA1c, and high sensitive C-reactive protein (hs-CRP) were assessed.
  
  
  RESULTS
  The IMT of CCA was significantly increased in NPC patients and carotid plaque was detected in 38 NPC patients (38/105, 36.2%). Significant risk factors for carotid plaques included age, duration after radiotherapy, and HbA1c levels. Age, duration after radiotherapy, hs-CRP, HbA1c, and platelet count positively correlated with IMT. The cut-off value of age and duration after radiotherapy for the presence of plaque was 52.5 years and 42.5 months, respectively. In NPC subjects, multiple linear regression analysis revealed that age, gender, duration after radiotherapy and platelet counts were independently associated with CCA IMT. After adjustments for age, gender and platelet counts, IMT increased in a linear manner with duration after radiotherapy.
  
  
  CONCLUSIONS
  Radiation-induced vasculopathy is a dynamic and progressive process due to late radiation effects. Extra-cranial color-coded duplex sonography can be part of routine follow-up in NPC patients aged ≥50 years at 40 months post-radiotherapy.
authors.forename: Tai-Lin
authors.initials: TL
authors.lastname: Huang
authors.forename: Hsuan-Chih
authors.initials: HC
authors.lastname: Hsu
authors.forename: Hui-Chun
authors.initials: HC
authors.lastname: Chen
authors.forename: Hsin-Ching
authors.initials: HC
authors.lastname: Lin
authors.forename: Chih-Yen
authors.initials: CY
authors.lastname: Chien
authors.forename: Fu-Min
authors.initials: FM
authors.lastname: Fang
authors.forename: Chih-Cheng
authors.initials: CC
authors.lastname: Huang
authors.forename: Hsueh-Wen
authors.initials: HW
authors.lastname: Chang
authors.forename: Wen-Neng
authors.initials: WN
authors.lastname: Chang
authors.forename: Chi-Ren
authors.initials: CR
authors.lastname: Huang
authors.forename: Nai-Wen
authors.initials: NW
authors.lastname: Tsai
authors.forename: Chia-Te
authors.initials: CT
authors.lastname: Kung
authors.forename: Hung-Chen
authors.initials: HC
authors.lastname: Wang
authors.forename: Wei-Che
authors.initials: WC
authors.lastname: Lin
authors.forename: Ben-Chung
authors.initials: BC
authors.lastname: Cheng
authors.forename: Yu-Jih
authors.initials: YJ
authors.lastname: Su
authors.forename: Ya-Ting
authors.initials: YT
authors.lastname: Chang
authors.forename: Chuang-Rung
authors.initials: CR
authors.lastname: Chang
authors.forename: Teng-Yeow
authors.initials: TY
authors.lastname: Tan
authors.forename: Cheng-Hsien
authors.initials: CH
authors.lastname: Lu
mesh_terms: D002277:Carcinoma; D002340:Carotid Artery Diseases / Q000209:etiology / Q000473:pathology*; D017536:Carotid Artery, Common / Q000473:pathology / Q000528:radiation effects*; D059168:Carotid Intima-Media Thickness; D016022:Case-Control Studies; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000532:radiotherapy*; D009367:Neoplasm Staging; D011379:Prognosis; D011446:Prospective Studies; D011832:Radiation Injuries / Q000209:etiology / Q000473:pathology*; D011878:Radiotherapy / Q000009:adverse effects*