title: Middle cerebral artery stenosis in patients with nasopharyngeal carcinoma after radiotherapy: the incidence of stenosis and the risk factors.
abstract: OBJECTIVE
  The purpose of the present study was to investigate the incidence of middle cerebral artery (MCA) stenosis by contrast-enhanced MR angiography (CE-MRA), and to evaluate the risk factors for significant (>50%) MCA stenosis in patients with nasopharyngeal carcinoma (NPC) after radiotherapy.
  
  
  METHODS
  116 patients with NPC after radiotherapy were recruited into the irradiation group to investigate the incidence and degree of MCA stenosis by CE-MRA. The results were compared with those of the control group, which comprised 57 newly diagnosed patients with NPC who did not receive radiotherapy. Furthermore, the risk factors for significant MCA stenosis were evaluated.
  
  
  RESULTS
  There was a higher incidence of MCA stenosis in the irradiation group than in the control group in terms of patient number (p = 0.000) and vessel involvement (p = 0.000), respectively. The incidence of significant MCA stenosis in the irradiation group was 8.6% (10/116 patients) and 5.2% (12/232 patients) in terms of patient number and vessel involvement, respectively. However, no significant MCA stenosis was found in the control group. Univariate analysis showed that hypercholesterolaemia, T(3-4) stage and longer time interval from radiotherapy were the risk factors related to significant MCA stenosis. Multivariate analysis demonstrated that only T stage was the independent risk factor for significant MCA stenosis development.
  
  
  CONCLUSIONS
  The results showed that radiation can cause MCA stenosis in patients with NPC after radiotherapy, especially in those with T(3-4) stage, and further study is needed.
  
  
  CONCLUSIONS
  Radiation-induced MCA stenosis exists in patients with NPC after radiotherapy, and its prevalence is more common in patients with clinical T(3-4) stage.
authors.affiliation: 1 Department of Radiology, the Second Affiliated Hospital of Soochow University, Suzhou, China.
authors.forename: Lijuan
authors.initials: L
authors.lastname: Zhou
authors.affiliation: 2 Department of Oncology & Radiotherapy, the Second Affiliated Hospital of Soochow University, Suzhou, China.
authors.forename: Pengfei
authors.initials: P
authors.lastname: Xing
authors.affiliation: 2 Department of Oncology & Radiotherapy, the Second Affiliated Hospital of Soochow University, Suzhou, China.
authors.forename: Li
authors.initials: L
authors.lastname: Zou
authors.affiliation: 1 Department of Radiology, the Second Affiliated Hospital of Soochow University, Suzhou, China.
authors.forename: Junkang
authors.initials: J
authors.lastname: Shen
authors.affiliation: 2 Department of Oncology & Radiotherapy, the Second Affiliated Hospital of Soochow University, Suzhou, China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Tian
authors.affiliation: 2 Department of Oncology & Radiotherapy, the Second Affiliated Hospital of Soochow University, Suzhou, China.
authors.forename: Xueguan
authors.initials: X
authors.lastname: Lu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001157:Arterial Occlusive Diseases / Q000453:epidemiology* / Q000473:pathology; D002277:Carcinoma; D015984:Causality; D002681:China / Q000453:epidemiology; D015897:Comorbidity; D003251:Constriction, Pathologic; D003287:Contrast Media; D005260:Female; D006801:Humans; D007089:Image Enhancement; D015994:Incidence; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D020768:Middle Cerebral Artery / Q000473:pathology*; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000453:epidemiology* / Q000532:radiotherapy*; D012307:Risk Factors; D055815:Young Adult
chemical_list: D003287:Contrast Media