Alexander Venjakob1, Michael Oertel2, Dominik Alexander Hering2, Christos Moustakis2, Uwe Haverkamp2, Hans Theodor Eich2. 1. Department of Radiation Oncology, University Hospital Muenster, Building A1, 1 Albert-Schweitzer-Campus, 48149, Muenster, Germany. Alexander.Venjakob@ukmuenster.de. 2. Department of Radiation Oncology, University Hospital Muenster, Building A1, 1 Albert-Schweitzer-Campus, 48149, Muenster, Germany.
Abstract
PURPOSE: This study aims to evaluate the best possible practice using hybrid volumetric modulated arc therapy (H-VMAT) for hypofractionated radiation therapy of breast cancer. Different combinations of H‑VMAT-a combination of three-dimensional radiotherapy (3D-CRT) and VMAT-were analyzed regarding planning target volume (PTV), dose coverage, and exposure to organs at risk (OAR). METHODS: Planning computed tomography scans were acquired in deep-inspiration breath-hold. A total of 520 treatment plans were calculated and evaluated for 40 patients, comprising six different H‑VMAT plans and a 3D-CRT plan as reference. H‑VMAT plans consisted of two treatment plans including 3D-CRT and VMAT. During H‑VMAT planning, the use of hard wedge filters (HWF) and beam energies were varied. The reference plans were planned with mixed beam energies and the inclusion/omission of HWF. RESULTS: Compared to the reference treatment plans, all H‑VMAT plans showed consistently better PTV dose coverage, conformity, and homogeneity. Additionally, OAR protection was significantly improved with several H‑VMAT combinations (p < 0.05). The comparison of different H‑VMAT combinations showed that inclusion of HWF in the base plan had a negative impact on PTV dose coverage, conformity, and OAR exposure. It also increased the planned monitor units and beam-on time. Advantages of using lower beam energies (6-MV photons) in both the base plan and in the VMAT supplementary dose were observed. CONCLUSION: The H‑VMAT technique is an effective possibility for generating homogenous and conformal dose distributions. With the right choice of H‑VMAT combination, superior OAR protection is achieved compared to 3D-CRT.
PURPOSE: This study aims to evaluate the best possible practice using hybrid volumetric modulated arc therapy (H-VMAT) for hypofractionated radiation therapy of breast cancer. Different combinations of H‑VMAT-a combination of three-dimensional radiotherapy (3D-CRT) and VMAT-were analyzed regarding planning target volume (PTV), dose coverage, and exposure to organs at risk (OAR). METHODS: Planning computed tomography scans were acquired in deep-inspiration breath-hold. A total of 520 treatment plans were calculated and evaluated for 40 patients, comprising six different H‑VMAT plans and a 3D-CRT plan as reference. H‑VMAT plans consisted of two treatment plans including 3D-CRT and VMAT. During H‑VMAT planning, the use of hard wedge filters (HWF) and beam energies were varied. The reference plans were planned with mixed beam energies and the inclusion/omission of HWF. RESULTS: Compared to the reference treatment plans, all H‑VMAT plans showed consistently better PTV dose coverage, conformity, and homogeneity. Additionally, OAR protection was significantly improved with several H‑VMAT combinations (p < 0.05). The comparison of different H‑VMAT combinations showed that inclusion of HWF in the base plan had a negative impact on PTV dose coverage, conformity, and OAR exposure. It also increased the planned monitor units and beam-on time. Advantages of using lower beam energies (6-MV photons) in both the base plan and in the VMAT supplementary dose were observed. CONCLUSION: The H‑VMAT technique is an effective possibility for generating homogenous and conformal dose distributions. With the right choice of H‑VMAT combination, superior OAR protection is achieved compared to 3D-CRT.
Authors: Stefanie Corradini; Hendrik Ballhausen; Helmut Weingandt; Philipp Freislederer; Stephan Schönecker; Maximilian Niyazi; Cristoforo Simonetto; Markus Eidemüller; Ute Ganswindt; Claus Belka Journal: Strahlenther Onkol Date: 2017-09-15 Impact factor: 3.621
Authors: Judit Boda-Heggemann; Antje-Christin Knopf; Anna Simeonova-Chergou; Hansjörg Wertz; Florian Stieler; Anika Jahnke; Lennart Jahnke; Jens Fleckenstein; Lena Vogel; Anna Arns; Manuel Blessing; Frederik Wenz; Frank Lohr Journal: Int J Radiat Oncol Biol Phys Date: 2015-12-17 Impact factor: 7.038
Authors: S M Bentzen; R K Agrawal; E G A Aird; J M Barrett; P J Barrett-Lee; S M Bentzen; J M Bliss; J Brown; J A Dewar; H J Dobbs; J S Haviland; P J Hoskin; P Hopwood; P A Lawton; B J Magee; J Mills; D A L Morgan; J R Owen; S Simmons; G Sumo; M A Sydenham; K Venables; J R Yarnold Journal: Lancet Date: 2008-03-19 Impact factor: 79.321