Jaegi Lee1,2, Jung-In Kim2,3,4,5, Sung-Joon Ye1,3, Hak Jae Kim3,4,6, Joel Carlson1,2, Jong Min Park2,3,4,5. 1. 1 Program in Biomedical Radiation Sciences, Department of Transdisciplinary Studies, Seoul National University Graduate School of Convergence Science and Technology, Seoul, Korea. 2. 2 Biomedical Research Institute, Seoul National University College of Medicine, Seoul, Korea. 3. 3 Department of Radiation Oncology, Seoul National University Hospital, Seoul, Korea. 4. 4 Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul, Korea. 5. 5 Center for Convergence Research on Robotics, Advanced Institutes of Convergence Technology, Suwon, Korea. 6. 6 Department of Radiation Oncology, Seoul National University College of Medicine, Seoul, Korea.
Abstract
OBJECTIVE: To evaluate the dosimetric effects of roll-rotational setup errors of stereotactic ablative radiotherapy (SABR) for lung cancer using volumetric modulated arc therapy (VMAT). METHODS: A total of 23 lung SABR cases were evaluated retrospectively. Each of the planning CT images was intentionally rotated by ±1°, ±2° and ±3°. After that, to simulate the translational couch correction, rotated CT images were moved along the x, y and z axis to match the centroid of the target volume in the rotated CT images with that in the original CT images. The differences in D95% and V100% of the target volume, D0.35cc of spinal cord, D0.35cc and D5cc of oesophagus and V20Gy of lung between the original and the rotated CT images were calculated. RESULTS: The average differences in D95% and V100% of target volume, D0.35cc of spinal cord, D0.35cc and D5cc of oesophagus and V20Gy of lung were -0.3% ± 0.4% and -0.7% ± 2.4%, 1.6 ± 27.9 cGy, -1.6 ± 37.6 cGy, 15.9 ± 25.3 cGy and 0.0% ± 0.1%, respectively. The dosimetric changes in organs at risk (OARs) near the target volume were sometimes considerable due to roll-rotational setup errors, despite the translational correction, and those were patient specific. CONCLUSION: In the case of coplanar VMAT for lung SABR, dosimetric changes to the target volume due to roll-rotational setup errors could be compensated by translational correction, whereas those to the OARs could not in some cases. ADVANCES IN KNOWLEDGE: Roll-rotational setup errors would increase the dose to OARs despite the translational correction.
OBJECTIVE: To evaluate the dosimetric effects of roll-rotational setup errors of stereotactic ablative radiotherapy (SABR) for lung cancer using volumetric modulated arc therapy (VMAT). METHODS: A total of 23 lung SABR cases were evaluated retrospectively. Each of the planning CT images was intentionally rotated by ±1°, ±2° and ±3°. After that, to simulate the translational couch correction, rotated CT images were moved along the x, y and z axis to match the centroid of the target volume in the rotated CT images with that in the original CT images. The differences in D95% and V100% of the target volume, D0.35cc of spinal cord, D0.35cc and D5cc of oesophagus and V20Gy of lung between the original and the rotated CT images were calculated. RESULTS: The average differences in D95% and V100% of target volume, D0.35cc of spinal cord, D0.35cc and D5cc of oesophagus and V20Gy of lung were -0.3% ± 0.4% and -0.7% ± 2.4%, 1.6 ± 27.9 cGy, -1.6 ± 37.6 cGy, 15.9 ± 25.3 cGy and 0.0% ± 0.1%, respectively. The dosimetric changes in organs at risk (OARs) near the target volume were sometimes considerable due to roll-rotational setup errors, despite the translational correction, and those were patient specific. CONCLUSION: In the case of coplanar VMAT for lung SABR, dosimetric changes to the target volume due to roll-rotational setup errors could be compensated by translational correction, whereas those to the OARs could not in some cases. ADVANCES IN KNOWLEDGE: Roll-rotational setup errors would increase the dose to OARs despite the translational correction.
Authors: Robert Timmerman; Rebecca Paulus; James Galvin; Jeffrey Michalski; William Straube; Jeffrey Bradley; Achilles Fakiris; Andrea Bezjak; Gregory Videtic; David Johnstone; Jack Fowler; Elizabeth Gore; Hak Choy Journal: JAMA Date: 2010-03-17 Impact factor: 56.272
Authors: Chin Loon Ong; Wilko F A R Verbakel; Johan P Cuijpers; Ben J Slotman; Frank J Lagerwaard; Suresh Senan Journal: Radiother Oncol Date: 2010-11-11 Impact factor: 6.280
Authors: Jean-Pierre Bissonnette; Thomas G Purdie; Jane A Higgins; Winnie Li; Andrea Bezjak Journal: Int J Radiat Oncol Biol Phys Date: 2008-12-25 Impact factor: 7.038
Authors: Inga S Grills; Geoffrey Hugo; Larry L Kestin; Ana Paula Galerani; K Kenneth Chao; Jennifer Wloch; Di Yan Journal: Int J Radiat Oncol Biol Phys Date: 2007-10-29 Impact factor: 7.038
Authors: James L Bedford; Vibeke Nordmark Hansen; Helen A McNair; Alexandra H Aitken; Juliet E C Brock; Alan P Warrington; Michael Brada Journal: Acta Oncol Date: 2008 Impact factor: 4.089
Authors: Sarah Barrett; Pierre Thirion; Dean Harper; Andrew J Simpkin; Michelle Leech; Kim Hickey; Laoise Ryan; Laure Marignol Journal: Rep Pract Oncol Radiother Date: 2019-09-04