title: Evaluation of liver function after proton beam therapy for hepatocellular carcinoma.
abstract: OBJECTIVE
  Our previous results for treatment of hepatocellular carcinoma with proton beam therapy (PBT) revealed excellent local control. In this study, we focused on the impact of PBT on normal liver function.
  
  
  METHODS
  The subjects were 259 patients treated with PBT at the University of Tsukuba between January 2001 and December 2007. We evaluated the Child-Pugh score pretreatment, on the final day of PBT, and 6, 12, and 24 months after treatment with PBT. Patients who had disease progression or who died with tumor progression at each evaluation point were excluded from the analysis to rule out an effect of tumor progression. An increase in the Child-Pugh score of 1 or more was defined as an adverse event.
  
  
  RESULTS
  Of the 259 patients, 241 had no disease progression on the final day of PBT, and 91 had no progression within 12 months after PBT. In univariate analysis, the percentage volumes of normal liver receiving at least 0, 10, 20, and 30 GyE in PBT (V0, 10, 20, and 30) were significantly associated with an increase of Child-Pugh score at 12 months after PBT. Of the 91 patients evaluated at 12 months, 66 had no increase of Child-Pugh score, 15 had a 1-point increase, and 10 had an increase of ≥2 points. For the Youden index, the optimal cut-offs for V0, V10, V20, and V30 were 30%, 20%, 26%, and 18%, respectively.
  
  
  CONCLUSIONS
  Our findings indicate that liver function after PBT is significantly related to the percentage volume of normal liver that is not irradiated. This suggests that further study of the relationship between liver function and PBT is required.
authors.affiliation: Proton Medical Research Center, University of Tsukuba, Tsukuba, Ibaraki, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Mizumoto
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Okumura
authors.forename: Takayuki
authors.initials: T
authors.lastname: Hashimoto
authors.forename: Kuniaki
authors.initials: K
authors.lastname: Fukuda
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Oshiro
authors.forename: Nobuyoshi
authors.initials: N
authors.lastname: Fukumitsu
authors.forename: Masato
authors.initials: M
authors.lastname: Abei
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kawaguchi
authors.forename: Yasutaka
authors.initials: Y
authors.lastname: Hayashi
authors.forename: Ayako
authors.initials: A
authors.lastname: Ohkawa
authors.forename: Haruko
authors.initials: H
authors.lastname: Hashii
authors.forename: Ayae
authors.initials: A
authors.lastname: Kanemoto
authors.forename: Takashi
authors.initials: T
authors.lastname: Moritake
authors.forename: Eriko
authors.initials: E
authors.lastname: Tohno
authors.forename: Koji
authors.initials: K
authors.lastname: Tsuboi
authors.forename: Takeji
authors.initials: T
authors.lastname: Sakae
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Sakurai
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D006528:Carcinoma, Hepatocellular / Q000503:physiopathology / Q000532:radiotherapy*; D018450:Disease Progression; D005260:Female; D006801:Humans; D008099:Liver / Q000502:physiology / Q000528:radiation effects*; D017093:Liver Failure / Q000209:etiology; D008113:Liver Neoplasms / Q000503:physiopathology / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D061766:Proton Therapy; D012189:Retrospective Studies; D011522:Protons
chemical_list: D011522:Protons