Ashlyn S Everett1, Bradford S Hoppe2, Debbie Louis3, Andrew M McDonald1, Christopher G Morris4, Nancy P Mendenhall4, Zuofeng Li5, Stella Flampouri5. 1. Department of Radiation Oncology, University of Alabama at Birmingham, Birmingham, Alabama. 2. Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, Florida; University of Florida Health Proton Therapy Institute, Jacksonville, Florida. Electronic address: bhoppe@floridaproton.org. 3. University of Florida Health Proton Therapy Institute, Jacksonville, Florida. 4. Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, Florida; University of Florida Health Proton Therapy Institute, Jacksonville, Florida. 5. Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, Florida.
Abstract
PURPOSE: Patients with lower mediastinal lymphoma (LML) benefit dosimetrically from proton therapy (PT) compared with intensity modulated radiation therapy (IMRT). The added dosimetric benefit of deep-inspiration breath-hold (DIBH) is unknown; therefore, we evaluated IMRT versus PT and free-breathing (FB) versus DIBH among patients with LML. METHODS AND MATERIALS: Twenty-one patients with LML underwent 4-dimensional computed tomography and 3 sequential DIBH scans at simulation. Involved-site radiation therapy target volumes and organ-at-risk contours were developed for both DIBH and FB scans. FB-IMRT, DIBH-IMRT, FB-PT, and DIBH-PT plans were generated for each patient for comparison. RESULTS: The median difference in lung volume between the DIBH and FB scans was 1275 mL; the average difference in clinical target volume was 5.7 mL. DIBH-IMRT produced a lower mean lung dose (10.8 vs 11.9 Gy; P < .001) than FB-IMRT, with no difference in mean heart dose (MHD; 16.1 vs 15.0 Gy; P = .992). Both PT plans produced a significantly lower mean dose to the lung, heart, left ventricle, esophagus, and nontarget body than DIBH-IMRT. DIBH-PT reduced the median MHD by 4.2 Gy (P < .0001); left ventricle dose by 5.1 Gy (P < .0001); and lung V5 by 26% (P < .0001) versus DIBH-IMRT. The 2 PT plans were comparable, with DIBH-PT reducing mean lung dose (7.0 vs 7.7 Gy; P = .063) and with no difference in MHD (10.3 vs 9.5 Gy; P = .992). CONCLUSIONS: Among patients with LML, DIBH (IMRT or PT) improved lung dosimetry over FB but had little influence on MHD. PT (DIBH and FB) significantly reduced lung, heart, esophagus, and nontarget body dose compared with DIBH IMRT, potentially reducing the risk of late complications.
PURPOSE:Patients with lower mediastinal lymphoma (LML) benefit dosimetrically from proton therapy (PT) compared with intensity modulated radiation therapy (IMRT). The added dosimetric benefit of deep-inspiration breath-hold (DIBH) is unknown; therefore, we evaluated IMRT versus PT and free-breathing (FB) versus DIBH among patients with LML. METHODS AND MATERIALS: Twenty-one patients with LML underwent 4-dimensional computed tomography and 3 sequential DIBH scans at simulation. Involved-site radiation therapy target volumes and organ-at-risk contours were developed for both DIBH and FB scans. FB-IMRT, DIBH-IMRT, FB-PT, and DIBH-PT plans were generated for each patient for comparison. RESULTS: The median difference in lung volume between the DIBH and FB scans was 1275 mL; the average difference in clinical target volume was 5.7 mL. DIBH-IMRT produced a lower mean lung dose (10.8 vs 11.9 Gy; P < .001) than FB-IMRT, with no difference in mean heart dose (MHD; 16.1 vs 15.0 Gy; P = .992). Both PT plans produced a significantly lower mean dose to the lung, heart, left ventricle, esophagus, and nontarget body than DIBH-IMRT. DIBH-PT reduced the median MHD by 4.2 Gy (P < .0001); left ventricle dose by 5.1 Gy (P < .0001); and lung V5 by 26% (P < .0001) versus DIBH-IMRT. The 2 PT plans were comparable, with DIBH-PT reducing mean lung dose (7.0 vs 7.7 Gy; P = .063) and with no difference in MHD (10.3 vs 9.5 Gy; P = .992). CONCLUSIONS: Among patients with LML, DIBH (IMRT or PT) improved lung dosimetry over FB but had little influence on MHD. PT (DIBH and FB) significantly reduced lung, heart, esophagus, and nontarget body dose compared with DIBH IMRT, potentially reducing the risk of late complications.
Authors: Amy C Moreno; Jillian R Gunther; Sarah Milgrom; C David Fuller; Tyler Williamson; Amy Liu; Richard Wu; X Ronald Zhu; Bouthaina S Dabaja; Chelsea C Pinnix Journal: Adv Radiat Oncol Date: 2020-08-25
Authors: Dennis Mah; Ellen Yorke; Entela Zemanaj; Zhiqiang Han; Haoyang Liu; Jobin George; Jason Lambiase; Christian Czmielewski; D Michael Lovelock; Andreas Rimner; Annemarie F Shepherd Journal: Med Dosim Date: 2021-08-21 Impact factor: 1.531
Authors: Matthew D Hall; Stephanie A Terezakis; John T Lucas; Eve Gallop-Evans; Karin Dieckmann; Louis S Constine; David Hodgson; Jamie E Flerlage; Monika L Metzger; Bradford S Hoppe Journal: Int J Radiat Oncol Biol Phys Date: 2021-08-12 Impact factor: 7.038