title: The significance of ICG-R15 in predicting hepatic toxicity in patients receiving radiotherapy for hepatocellular carcinoma.
abstract: OBJECTIVE
  To evaluate whether the retention rate of indocyanine green 15 min after administration (ICG-R15) could predict radiation hepatotoxicity in patients treated with radiotherapy (RT) for hepatocellular carcinoma (HCC).
  
  
  METHODS
  We retrospectively reviewed data of 146 HCC patients treated with RT between February 1994 and December 2008. The ICG-R15 was measured within 1 month prior to the start of RT. Radiation hepatotoxicity was evaluated by incidence of radiation-induced liver disease (RILD) between 2 weeks and 3 months after completion of RT. We analysed the correlation between the incidence rate of RILD and the ICG-R15 before RT (pre-RT ICG-R15).
  
  
  RESULTS
  The classic and non-classic RILD occurred in 15 patients (10.3%): classic type in five patients (3.4%) and non-classic RILD in 10 patients (6.9%). A positive correlation was shown between the probability of RILD and increase in pre-RT ICG-R15 (P < 0.0001). Univariate analysis indicated that cut-off value of pre-RT ICG-R15 could predict RILD significantly. The incidence of RILD for the patients with 22% or higher pre-RT ICG-R15 levels was 40.7% as compared to 3.4% for those with levels lower than 22% (P < 0.0001). There was no clinical factor that significantly affected RILD in univariate analysis. Multivariate analysis indicated that the pre-RT ICG-R15 value was the only significant factor affecting RILD (P < 0.0001).
  
  
  CONCLUSIONS
  These results suggest that pre-RT ICG-R15 could be a useful factor in predicting radiation hepatotoxicity in HCC patients treated with RT.
authors.affiliation: Department of Radiation Oncology, Yonsei University Health System, Seoul, Korea.
authors.forename: Hong In
authors.initials: HI
authors.lastname: Yoon
authors.forename: Woong Sub
authors.initials: WS
authors.lastname: Koom
authors.forename: Ik Jae
authors.initials: IJ
authors.lastname: Lee
authors.forename: Kyoungkeun
authors.initials: K
authors.lastname: Jeong
authors.forename: Yoonsun
authors.initials: Y
authors.lastname: Chung
authors.forename: Ja Kyung
authors.initials: JK
authors.lastname: Kim
authors.forename: Kwan Sik
authors.initials: KS
authors.lastname: Lee
authors.forename: Kwang-Hyub
authors.initials: KH
authors.lastname: Han
authors.forename: Jinsil
authors.initials: J
authors.lastname: Seong
mesh_terms: D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000532:radiotherapy*; D004396:Coloring Agents; D005260:Female; D006801:Humans; D007208:Indocyanine Green; D008107:Liver Diseases / Q000209:etiology; D008113:Liver Neoplasms / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D011832:Radiation Injuries / Q000209:etiology; D011878:Radiotherapy / Q000009:adverse effects*; D012189:Retrospective Studies
chemical_list: D004396:Coloring Agents; D007208:Indocyanine Green