Joe Y Chang1, Heng Li2, X Ronald Zhu2, Zhongxing Liao3, Lina Zhao3, Amy Liu2, Yupeng Li4, Narayan Sahoo2, Falk Poenisch2, Daniel R Gomez3, Richard Wu2, Michael Gillin2, Xiaodong Zhang5. 1. Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas. Electronic address: jychang@mdanderson.org. 2. Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas. 3. Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas. 4. Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas; Applied Research, Varian Medical Systems, Palo Alto, California. 5. Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas. Electronic address: xizhang@mdanderson.org.
Abstract
PURPOSE: Intensity modulated proton therapy (IMPT) can improve dose conformality and better spare normal tissue over passive scattering techniques, but range uncertainties complicate its use, particularly for moving targets. We report our early experience with IMPT for thoracic malignancies in terms of motion analysis and management, plan optimization and robustness, and quality assurance. METHODS AND MATERIALS: Thirty-four consecutive patients with lung/mediastinal cancers received IMPT to a median 66 Gy(relative biological equivalence [RBE]). All patients were able to undergo definitive radiation therapy. IMPT was used when the treating physician judged that IMPT conferred a dosimetric advantage; all patients had minimal tumor motion (<5 mm) and underwent individualized tumor-motion dose-uncertainty analysis and 4-dimensional (4D) computed tomographic (CT)-based treatment simulation and motion analysis. Plan robustness was optimized by using a worst-case scenario method. All patients had 4D CT repeated simulation during treatment. RESULTS: IMPT produced lower mean lung dose (MLD), lung V5 and V20, heart V40, and esophageal V60 than did IMRT (P<.05) and lower MLD, lung V20, and esophageal V60 than did passive scattering proton therapy (PSPT) (P<.05). D5 to the gross tumor volume and clinical target volume was higher with IMPT than with intensity modulated radiation therapy or PSPT (P<.05). All cases were analyzed for beam-angle-specific motion, water-equivalent thickness, and robustness. Beam angles were chosen to minimize the effect of respiratory motion and avoid previously treated regions, and the maximum deviation from the nominal dose-volume histogram values was kept at <5% for the target dose and met the normal tissue constraints under a worst-case scenario. Patient-specific quality assurance measurements showed that a median 99% (range, 95% to 100%) of the pixels met the 3% dose/3 mm distance criteria for the γ index. Adaptive replanning was used for 9 patients (26.5%). CONCLUSIONS: IMPT using 4D CT-based planning, motion management, and optimization was implemented successfully and met our quality assurance parameters for treating challenging thoracic cancers.
PURPOSE: Intensity modulated proton therapy (IMPT) can improve dose conformality and better spare normal tissue over passive scattering techniques, but range uncertainties complicate its use, particularly for moving targets. We report our early experience with IMPT for thoracic malignancies in terms of motion analysis and management, plan optimization and robustness, and quality assurance. METHODS AND MATERIALS: Thirty-four consecutive patients with lung/mediastinal cancers received IMPT to a median 66 Gy(relative biological equivalence [RBE]). All patients were able to undergo definitive radiation therapy. IMPT was used when the treating physician judged that IMPT conferred a dosimetric advantage; all patients had minimal tumor motion (<5 mm) and underwent individualized tumor-motion dose-uncertainty analysis and 4-dimensional (4D) computed tomographic (CT)-based treatment simulation and motion analysis. Plan robustness was optimized by using a worst-case scenario method. All patients had 4D CT repeated simulation during treatment. RESULTS:IMPT produced lower mean lung dose (MLD), lung V5 and V20, heart V40, and esophageal V60 than did IMRT (P<.05) and lower MLD, lung V20, and esophageal V60 than did passive scattering proton therapy (PSPT) (P<.05). D5 to the gross tumor volume and clinical target volume was higher with IMPT than with intensity modulated radiation therapy or PSPT (P<.05). All cases were analyzed for beam-angle-specific motion, water-equivalent thickness, and robustness. Beam angles were chosen to minimize the effect of respiratory motion and avoid previously treated regions, and the maximum deviation from the nominal dose-volume histogram values was kept at <5% for the target dose and met the normal tissue constraints under a worst-case scenario. Patient-specific quality assurance measurements showed that a median 99% (range, 95% to 100%) of the pixels met the 3% dose/3 mm distance criteria for the γ index. Adaptive replanning was used for 9 patients (26.5%). CONCLUSIONS:IMPT using 4D CT-based planning, motion management, and optimization was implemented successfully and met our quality assurance parameters for treating challenging thoracic cancers.
Authors: Yupeng Li; Laleh Kardar; Xiaoqiang Li; Heng Li; Wenhua Cao; Joe Y Chang; Li Liao; Ronald X Zhu; Narayan Sahoo; Michael Gillin; Zhongxing Liao; Ritsuko Komaki; James D Cox; Gino Lim; Xiaodong Zhang Journal: Med Phys Date: 2014-02 Impact factor: 4.071
Authors: Yixiu Kang; Xiaodong Zhang; Joe Y Chang; He Wang; Xiong Wei; Zhongxing Liao; Ritsuko Komaki; James D Cox; Peter A Balter; Helen Liu; X Ronald Zhu; Radhe Mohan; Lei Dong Journal: Int J Radiat Oncol Biol Phys Date: 2007-03-01 Impact factor: 7.038
Authors: H Helen Liu; Peter Balter; Teresa Tutt; Bum Choi; Joy Zhang; Catherine Wang; Melinda Chi; Dershan Luo; Tinsu Pan; Sandeep Hunjan; George Starkschall; Isaac Rosen; Karl Prado; Zhongxing Liao; Joe Chang; Ritsuko Komaki; James D Cox; Radhe Mohan; Lei Dong Journal: Int J Radiat Oncol Biol Phys Date: 2007-03-29 Impact factor: 7.038
Authors: Li Liao; Gino J Lim; Yupeng Li; Juan Yu; Narayan Sahoo; Heng Li; Michael Gillin; X Ronald Zhu; Anita Mahajan; Steven J Frank; David R Grosshans; Quynh-Nhu Nguyen; Daniel Gomez; Xiaodong Zhang Journal: Int J Part Ther Date: 2016-12-30
Authors: Joe Y Chang; Vivek Verma; Ming Li; Wencheng Zhang; Ritsuko Komaki; Charles Lu; Pamela K Allen; Zhongxing Liao; James Welsh; Steven H Lin; Daniel Gomez; Melenda Jeter; Michael O'Reilly; Ronald X Zhu; Xiaodong Zhang; Heng Li; Radhe Mohan; John V Heymach; Ara A Vaporciyan; Stephen Hahn; James D Cox Journal: JAMA Oncol Date: 2017-08-10 Impact factor: 31.777