title: Relationship between individual radiosensitivity and radiation encephalopathy of nasopharyngeal carcinoma after radiotherapy.
abstract: OBJECTIVE
  To analyze the relationship between individual radiosensitivity and the morbidity and severity of radiation encephalopathy (RE) induced by radiotherapy of nasopharyngeal carcinoma (NPC) patients.
  
  
  METHODS
  In this study, 26 patients with RE (experimental group) and 26 patients without RE (control group) after radiotherapy of NPC were included. The experimental group was divided into two subgroups, that is, group 1 with 1-2 grade and group 2 with 3-4 grade, according to the RTOG/EORTC Score. Individual radiosensitivity was determined by the total chromosomal aberration rate measured in in vitro irradiated lymphocytes by a metaphase detection technique. Chromosomal aberration rate was correlated to development of RE in order to investigate the relationship between radiosensitivity and RE.
  
  
  RESULTS
  The total chromosomal aberration rate was found to be a risk factor for the onset of RE. The total chromosomal aberration rate was positively correlated to the severity of RE. Patients with a high radiosensitivity had shorter latency than those with a low or intermediate radiosensitivity.
  
  
  CONCLUSIONS
  In NPC patients, individual radiosensitivity as determined by the proportion of lethal chromosomal aberrations in in vitro irradiated lymphocytes might be associated with the development of RE and has the potential to predict the morbidity and severity of RE.
authors.affiliation: Department of Neurology, The Second Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China. yameitang@hotmail.com
authors.forename: Yamei
authors.initials: Y
authors.lastname: Tang
authors.forename: Yinyin
authors.initials: Y
authors.lastname: Zhang
authors.forename: Ling
authors.initials: L
authors.lastname: Guo
authors.forename: Ying
authors.initials: Y
authors.lastname: Peng
authors.forename: Qingliang
authors.initials: Q
authors.lastname: Luo
authors.forename: Yigang
authors.initials: Y
authors.lastname: Xing
mesh_terms: D000328:Adult; D000368:Aged; D001921:Brain / Q000528:radiation effects*; D001925:Brain Damage, Chronic / Q000209:etiology*; D002869:Chromosome Aberrations; D002877:Chromosomes, Human / Q000528:radiation effects; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000532:radiotherapy*; D011832:Radiation Injuries / Q000209:etiology*; D011836:Radiation Tolerance; D011879:Radiotherapy Dosage; D012306:Risk