PURPOSE: The aim of this study was to evaluate the feasibility and dose distribution of two different stereotactic body radiation therapy (SBRT) techniques, isocentric RapidArc (RA) and non-isocentric CyberKnife (CK), for the treatment of localized prostate cancer.
METHODS: Two groups of patients (Groups 1 and 2 with ten patients per group) treated with CK were re-planned with RA. The patients were grouped according to the rectum constraint used (Group1, maximum dose for rectum; Group 2, dose-volume histogram for rectum). The prescription dose was 37.5 Gy in five fractions. The two SBRT techniques were compared by target coverage, normal tissue sparing, and dose distribution parameters. Monitor units (MUs) and the delivery time were likewise compared to assess delivery efficiency.
RESULTS: The RA plans consistently exhibited superior PTV coverage and better rectum sparing at low doses in the both groups. The conformity and heterogeneity indices of the RA plans were better than the CK plans. Additionally, the RA plans resulted in fewer low-dose regions, lower MUs, and faster delivery times than the CK plans.
CONCLUSIONS: The good dosimetric distribution and shorter delivery time make RA an attractive SBRT technique for the treatment of localized prostate cancer.
Written by:
Lin YW, Lin KH, Ho HW, Lin HM, Lin LC, Lee SP, Chui CS. Are you the author?
Department of Radiation Oncology, Chi Mei Medical Center, Tainan, Taiwan; Institute of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan; School of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Radiation Oncology, Chi Mei Medical Center, Tainan, Taiwan; School of Medicine, Taipei Medical University, Taipei, Taiwan; Department of Radiation Oncology, David Geffen School of Medicine of The University of California Los Angeles, Los Angeles, CA, USA; Department of Medical Physics, Koo Foundation Sun Yat-Sen Cancer Center, Taipei, Taiwan.
Reference: Phys Med. 2014 Apr 9. pii: S1120-1797(14)00052-0.
doi: 10.1016/j.ejmp.2014.03.008
PubMed Abstract
PMID: 24726212
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