Daniel Richter1, Nami Saito2, Naved Chaudhri3, Martin Härtig4, Malte Ellerbrock3, Oliver Jäkel5, Stephanie E Combs4, Daniel Habermehl4, Klaus Herfarth4, Marco Durante1, Christoph Bert6. 1. GSI Helmholtzzentrum für Schwerionenforschung, Department of Biophysics, Darmstadt, Germany; TU Darmstadt, Darmstadt, Germany. 2. GSI Helmholtzzentrum für Schwerionenforschung, Department of Biophysics, Darmstadt, Germany. 3. Heidelberg Ion-Beam Therapy Center, Department of Medical Physics, Heidelberg, Germany. 4. University Hospital of Heidelberg, Department of Radiation Oncology, Heidelberg, Germany. 5. Heidelberg Ion-Beam Therapy Center, Department of Medical Physics, Heidelberg, Germany; University Hospital of Heidelberg, Department of Radiation Oncology, Heidelberg, Germany. 6. GSI Helmholtzzentrum für Schwerionenforschung, Department of Biophysics, Darmstadt, Germany; University Clinic Erlangen and Friedrich-Alexander University Erlangen-Nürnberg, Department of Radiation Oncology, Erlangen, Germany. Electronic address: christoph.bert@uk-erlangen.de.
Abstract
PURPOSE: Estimation of the actual delivered 4-dimensional (4D) dose in treatments of patients with mobile hepatocellular cancer with scanned carbon ion beam therapy. METHODS AND MATERIALS: Six patients were treated with 4 fractions to a total relative biological effectiveness (RBE)-weighted dose of 40 Gy (RBE) using a single field. Respiratory motion was addressed by dedicated margins and abdominal compression (5 patients) or gating (1 patient). 4D treatment dose reconstructions based on the treatment records and the measured motion monitoring data were performed for the single-fraction dose and a total of 17 fractions. To assess the impact of uncertainties in the temporal correlation between motion trajectory and beam delivery sequence, 3 dose distributions for varying temporal correlation were calculated per fraction. For 3 patients, the total treatment dose was formed from the fractional distributions using all possible combinations. Clinical target volume (CTV) coverage was analyzed using the volumes receiving at least 95% (V95) and 107% (V107) of the planned doses. RESULTS: 4D dose reconstruction based on daily measured data is possible in a clinical setting. V95 and V107 values for the single fractions ranged between 72% and 100%, and 0% and 32%, respectively. The estimated total treatment dose to the CTV exhibited improved and more robust dose coverage (mean V95 > 87%, SD < 3%) and overdose (mean V107 < 4%, SD < 3%) with respect to the single-fraction dose for all analyzed patients. CONCLUSIONS: A considerable impact of interplay effects on the single-fraction CTV dose was found for most of the analyzed patients. However, due to the fractionated treatment, dose heterogeneities were substantially reduced for the total treatment dose. 4D treatment dose reconstruction for scanned ion beam therapy is technically feasible and may evolve into a valuable tool for dose assessment.
PURPOSE: Estimation of the actual delivered 4-dimensional (4D) dose in treatments of patients with mobile hepatocellular cancer with scanned carbon ion beam therapy. METHODS AND MATERIALS: Six patients were treated with 4 fractions to a total relative biological effectiveness (RBE)-weighted dose of 40 Gy (RBE) using a single field. Respiratory motion was addressed by dedicated margins and abdominal compression (5 patients) or gating (1 patient). 4D treatment dose reconstructions based on the treatment records and the measured motion monitoring data were performed for the single-fraction dose and a total of 17 fractions. To assess the impact of uncertainties in the temporal correlation between motion trajectory and beam delivery sequence, 3 dose distributions for varying temporal correlation were calculated per fraction. For 3 patients, the total treatment dose was formed from the fractional distributions using all possible combinations. Clinical target volume (CTV) coverage was analyzed using the volumes receiving at least 95% (V95) and 107% (V107) of the planned doses. RESULTS: 4D dose reconstruction based on daily measured data is possible in a clinical setting. V95 and V107 values for the single fractions ranged between 72% and 100%, and 0% and 32%, respectively. The estimated total treatment dose to the CTV exhibited improved and more robust dose coverage (mean V95 > 87%, SD < 3%) and overdose (mean V107 < 4%, SD < 3%) with respect to the single-fraction dose for all analyzed patients. CONCLUSIONS: A considerable impact of interplay effects on the single-fraction CTV dose was found for most of the analyzed patients. However, due to the fractionated treatment, dose heterogeneities were substantially reduced for the total treatment dose. 4D treatment dose reconstruction for scanned ion beam therapy is technically feasible and may evolve into a valuable tool for dose assessment.
Authors: John Gordon Eley; Wayne David Newhauser; Daniel Richter; Robert Lüchtenborg; Nami Saito; Christoph Bert Journal: Phys Med Biol Date: 2015-02-04 Impact factor: 3.609
Authors: Constantin Dreher; Christian Scholz; Mira Pommer; Stephan Brons; Hannah Prokesch; Swantje Ecker; Jürgen Debus; Oliver Jäkel; Stephanie E Combs; Daniel Habermehl Journal: PLoS One Date: 2016-10-13 Impact factor: 3.240
Authors: James E Younkin; Danairis Hernandez Morales; Jiajian Shen; Xiaoning Ding; Joshua B Stoker; Nathan Y Yu; Terence T Sio; Thomas B Daniels; Martin Bues; Mirek Fatyga; Steven E Schild; Wei Liu Journal: Med Phys Date: 2021-07-29 Impact factor: 4.506
Authors: Constantin Dreher; Daniel Habermehl; Swantje Ecker; Stephan Brons; Rami El-Shafie; Oliver Jäkel; Jürgen Debus; Stephanie E Combs Journal: Radiat Oncol Date: 2015-11-21 Impact factor: 3.481