title: Dosimetric parameter predicting the deterioration of hepatic function after helical tomotherapy in patients with unresectable locally advanced hepatocellular carcinoma.
abstract: BACKGROUND
  The purpose of this study was to identify parameters capable of predicting the deterioration of hepatic function after helical tomotherapy in patients with unresectable locally advanced hepatocellular carcinoma.
  
  
  METHODS
  Between March 2006 and February 2012, 72 patients were eligible for this study. All patients received hypofractionated radiotherapy using the TomoTherapy Hi-Art (TomoTherapy, Madison, WI, USA) at Seoul St. Mary's Hospital and Incheon St. Mary's Hospital, the Catholic University of Korea. The radiation dose was a median 50 Gy (range: 40-50 Gy) in 10 fractions to 95% of the planning target volume. Radiation-induced hepatic toxicity was defined as an increase of at least 2 points in the Child-Pugh (CP) score within 3 months after completion of helical tomotherapy.
  
  
  RESULTS
  An increase of at least 2 points in the CP score occurred in 32 of the 72 patients (44.4%). Multivariate logistic regression analysis revealed that pretreatment CP class and V15Gy were significant parameters associated with an increase in CP score (p = 0.009 and p < 0.001, respectively). The area under receiver operating characteristic curve was 0.863 for V15Gy (p < 0.001). For V15Gy, with a cutoff value of 43.2%, the accuracy was 0.806 (58/72) with a sensitivity of 0.938 and a specificity of 0.725.
  
  
  CONCLUSIONS
  An increase of at least 2 points in the CP score is a radiation dose-limiting factor, and the non-target normal liver receiving a dose more than 15 Gy (V15Gy) should be <43.2% to reduce the risk of the deterioration of hepatic function.
authors.affiliation: Department of Radiation Oncology, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Seok Hyun
authors.initials: SH
authors.lastname: Son
authors.forename: Chul Seung
authors.initials: CS
authors.lastname: Kay
authors.forename: Jin Ho
authors.initials: JH
authors.lastname: Song
authors.forename: Sea-Won
authors.initials: SW
authors.lastname: Lee
authors.forename: Byung Ock
authors.initials: BO
authors.lastname: Choi
authors.forename: Young Nam
authors.initials: YN
authors.lastname: Kang
authors.forename: Jeong Won
authors.initials: JW
authors.lastname: Jang
authors.forename: Seung Kew
authors.initials: SK
authors.lastname: Yoon
authors.forename: Hong Seok
authors.initials: HS
authors.lastname: Jang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D006528:Carcinoma, Hepatocellular / Q000532:radiotherapy*; D005260:Female; D006801:Humans; D008099:Liver / Q000473:pathology / Q000503:physiopathology* / Q000528:radiation effects; D008113:Liver Neoplasms / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D015999:Multivariate Analysis; D011336:Probability; D012372:ROC Curve; D011832:Radiation Injuries / Q000175:diagnosis; D011874:Radiometry / Q000379:methods*; D011879:Radiotherapy Dosage; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods; D055815:Young Adult