title: Application of active breathing control in 3-dimensional conformal radiation therapy for hepatocellular carcinoma: the feasibility and benefit.
abstract: OBJECTIVE
  To investigate the feasibility and effectiveness of utilizing active breathing coordinator (ABC) in 3DCRT for HCC.
  
  
  METHODS
  A dosimetric comparison between the free-breathing (FB) plan and ABC plan in HCC 3DCRT was performed. Set-up errors and reproducibility of diaphragm position using ABC were measured, and patients' acceptance was also recorded.
  
  
  RESULTS
  From April 2005 to February 2007, 28 HCC were irradiated with ABC and they tolerated ABC well. The mean dose to normal liver was reduced from 16.9Gy in FB plan to 14.3Gy in ABC plan. PTV for ABC and FB plans were 529cm(3) and 781cm(3), respectively, and V(23) were reduced from 45% to 30%. The predicted incidences of radiation-induced liver disease by Lyman model were 1% and 2.5%, respectively, in favor of ABC plan. The systematic and random errors for the ABC and FB plans were 1.2mm vs. 4.7mm, 1.6mm vs. 3.5mm, and 1.8mm vs. 2.7mm, respectively, in cranio-caudal, anterior-posterior, and left-right directions. The average intrafraction reproducibility of diaphragm position in cranio-caudal direction was 1.6mm, and the interfraction, 6.7mm.
  
  
  CONCLUSIONS
  The utilization of ABC in HCC 3DCRT is feasible, and can reduce liver irradiation.
authors.affiliation: Department of Radiation Oncology, Fudan University Cancer Hospital, Shanghai, China.
authors.forename: Jian-Dong
authors.initials: JD
authors.lastname: Zhao
authors.forename: Zhi-Yong
authors.initials: ZY
authors.lastname: Xu
authors.forename: Ji
authors.initials: J
authors.lastname: Zhu
authors.forename: Jian-Jian
authors.initials: JJ
authors.lastname: Qiu
authors.forename: Wei-Gang
authors.initials: WG
authors.lastname: Hu
authors.forename: Lan-Fei
authors.initials: LF
authors.lastname: Cheng
authors.forename: Xiao-Jian
authors.initials: XJ
authors.lastname: Zhang
authors.forename: Guo-Liang
authors.initials: GL
authors.lastname: Jiang
mesh_terms: D000328:Adult; D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000532:radiotherapy*; D005260:Female; D006801:Humans; D008099:Liver / Q000528:radiation effects; D008113:Liver Neoplasms / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D009068:Movement; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D020266:Radiotherapy, Conformal / Q000379:methods; D015203:Reproducibility of Results; D012119:Respiration