title: Fractionated changes in prostate cancer radiotherapy using cone-beam computed tomography.
abstract: The high mobility of the bladder and the rectum causes uncertainty in radiation doses prescribed to patients with prostate cancer who undergo radiotherapy (RT) multifraction treatments. The purpose of this study was to estimate the dose received by the bladder, rectum, and prostate from multifraction treatments using daily cone-beam computed tomography (CBCT). Overall, 28 patients with prostate cancer who planned to receive radiation treatments were enrolled in the study. The acquired CBCT before the treatment delivery was registered with the planning CT to map the dose distribution used in the treatment plan for estimating the received dose during clinical treatment. For all 28 patients with 112 data sets, the mean percentage differences (± standard deviation) in the volume and radiation dose were 44% (± 41) and 18% (± 17) for the bladder, 20% (± 21) and 2% (± 2) for the prostate, and 36% (± 29) and 22% (± 15) for the rectum, respectively. Substantial differences between the volumes and radiation dose and those specified in treatment plans were observed. Besides the use of image-guided RT to improve patient setup accuracy, further consideration of large changes in bladder and rectum volumes is strongly suggested when using external beam radiation for prostate cancer.
authors: Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung City, Taiwan; Department of Biomedical Informatics, Asia University, Taichung City, Taiwan. Electronic address: tzungchi.huang@mail.cmu.edu.tw.
authors: Tzung-Chi
authors: TC
authors: Huang
authors: Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung City, Taiwan.
authors: Kuei-Ting
authors: KT
authors: Chou
authors: Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung City, Taiwan; Department of Biomedical Informatics, Asia University, Taichung City, Taiwan.
authors: Shih-Neng
authors: SN
authors: Yang
authors: Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung City, Taiwan.
authors: Chih-Kai
authors: CK
authors: Chang
authors: Department of Radiation Oncology, China Medical University Hospital, Taichung City, Taiwan.
authors: Ji-An
authors: JA
authors: Liang
authors: Department of Radiation Oncology, Moffitt Cancer Center, Tampa, FL.
authors: Geoffrey
authors: G
authors: Zhang
mesh_terms: D054893:Cone-Beam Computed Tomography / Q000379:methods*; D019583:Dose Fractionation, Radiation; D006801:Humans; D008297:Male; D059351:Organ Sparing Treatments / Q000379:methods*; D058958:Organs at Risk / Q000000981:diagnostic imaging / Q000528:radiation effects; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy*; D011835:Radiation Protection / Q000379:methods*; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods; D020266:Radiotherapy, Conformal / Q000379:methods; D061089:Radiotherapy, Image-Guided / Q000379:methods*; D012007:Rectum / Q000000981:diagnostic imaging / Q000528:radiation effects; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D016896:Treatment Outcome; D001743:Urinary Bladder / Q000000981:diagnostic imaging / Q000528:radiation effects
keywords: Multifraction; Prostate cancer; Radiation treatments