Eelco Lens1, Astrid van der Horst2, Eva Versteijne2, Geertjan van Tienhoven2, Arjan Bel2. 1. Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. Electronic address: e.lens@amc.uva.nl. 2. Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
Abstract
PURPOSE: The midventilation (midV) approach can be used to take respiratory-induced pancreatic tumor motion into account during radiation therapy. In this study, the dosimetric consequences for organs at risk and tumor coverage of using a midV approach compared with using an internal target volume (ITV) were investigated. METHODS AND MATERIALS: For each of the 18 patients, 2 treatment plans (25 × 2.0 Gy) were created, 1 using an ITV and 1 using a midV approach. The midV dose distribution was blurred using the respiratory-induced motion from 4-dimensional computed tomography. The resulting planning target volume (PTV) coverage for this blurred dose distribution was analyzed; PTV coverage was required to be at least V95% >98%. In addition, the change in PTV size and the changes in V10Gy, V20Gy, V30Gy, V40Gy, Dmean and D2cc for the stomach and for the duodenum were analyzed; differences were tested for significance using the Wilcoxon signed-rank test. RESULTS: Using a midV approach resulted in sufficient target coverage. A highly significant PTV size reduction of 13.9% (P<.001) was observed. Also, all dose parameters for the stomach and duodenum, except the D2cc of the duodenum, improved significantly (P≤.002). CONCLUSIONS: By using the midV approach to account for respiratory-induced tumor motion, a significant PTV reduction and significant dose reductions to the stomach and to the duodenum can be achieved when irradiating pancreatic tumors.
PURPOSE: The midventilation (midV) approach can be used to take respiratory-induced pancreatic tumor motion into account during radiation therapy. In this study, the dosimetric consequences for organs at risk and tumor coverage of using a midV approach compared with using an internal target volume (ITV) were investigated. METHODS AND MATERIALS: For each of the 18 patients, 2 treatment plans (25 × 2.0 Gy) were created, 1 using an ITV and 1 using a midV approach. The midV dose distribution was blurred using the respiratory-induced motion from 4-dimensional computed tomography. The resulting planning target volume (PTV) coverage for this blurred dose distribution was analyzed; PTV coverage was required to be at least V95% >98%. In addition, the change in PTV size and the changes in V10Gy, V20Gy, V30Gy, V40Gy, Dmean and D2cc for the stomach and for the duodenum were analyzed; differences were tested for significance using the Wilcoxon signed-rank test. RESULTS: Using a midV approach resulted in sufficient target coverage. A highly significant PTV size reduction of 13.9% (P<.001) was observed. Also, all dose parameters for the stomach and duodenum, except the D2cc of the duodenum, improved significantly (P≤.002). CONCLUSIONS: By using the midV approach to account for respiratory-induced tumor motion, a significant PTV reduction and significant dose reductions to the stomach and to the duodenum can be achieved when irradiating pancreatic tumors.
Authors: Z van Kesteren; J K Veldman; M J Parkes; M F Stevens; P Balasupramaniam; J G van den Aardweg; G van Tienhoven; A Bel; I W E M van Dijk Journal: Radiat Oncol Date: 2022-05-21 Impact factor: 4.309
Authors: Eva Versteijne; Oliver J Gurney-Champion; Astrid van der Horst; Eelco Lens; M Willemijn Kolff; Jeroen Buijsen; Gati Ebrahimi; Karen J Neelis; Coen R N Rasch; Jaap Stoker; Marcel van Herk; Arjan Bel; Geertjan van Tienhoven Journal: Radiat Oncol Date: 2017-03-23 Impact factor: 3.481
Authors: Sophie C Huijskens; Irma W E M van Dijk; Jorrit Visser; Brian V Balgobind; Coen R N Rasch; Tanja Alderliesten; Arjan Bel Journal: Radiat Oncol Date: 2018-10-11 Impact factor: 3.481