TY - JOUR
T1 - Validation of dose painting of lung tumours using alanine/EPR dosimetry
AU - Knudtsen, Ingerid Skjei
AU - Svestad, Jorund Graadal
AU - Sande, Erlend Peter Skaug
AU - Rekstad, Bernt Louni
AU - Rodal, Jan
AU - van Elmpt, Wouter
AU - Öllers, Michel
AU - Hole, Eli Olaug
AU - Malinen, Eirik
PY - 2016/3/21
Y1 - 2016/3/21
N2 - Biologic image guided radiotherapy (RT) with escalated doses to tumour sub volumes challenges today's RT dose planning and delivery systems. In this phantom study, we verify the capability of a clinical dose planning and delivery system to deliver an F-18-FDG-PET based dose painted treatment plan to a lung tumour. Furthermore, we estimate the uncertainties of the dose painted treatment compared to conventional RT plans. An anthropomorphic thorax phantom of polystyrene and polyurethane was constructed based on CT images of a lung cancer patient. 101 EPR/alanine dosimeters were placed in separate cavities within the phantom. IMRT and VMAT plans were generated in Eclipse (version 10.0, Analytical Anisotropic Algorithm version 10.2.28, Varian Medical Systems, Inc.) for 6 and 15 MV photons, based on F-18-FDG-PET/CT images of the patient. A boost dose of 3.8 Gy/fraction was given to the F-18-FDG-avid region (biological planning volume; BTV), whereas 3.1 Gy/fraction was planned to the planning target volume (PTV, excluding the BTV). For the homogenous plans, 3.2 Gy/fraction was given to the PTV. Irradiation of the phantom was carried out at a Varian Trilogy linear accelerator (Varian Medical Systems, Inc.). Uncertainties involved in treatment planning and delivery were estimated from portal dosimetry gamma evalutation. Measured and calculated doses were compared by Bland-Altmann analysis. For all treatment plans, all dose-volume objectives could be achieved in the treatment planning system. The mean absolute differences between calculated and measured doses were small (
AB - Biologic image guided radiotherapy (RT) with escalated doses to tumour sub volumes challenges today's RT dose planning and delivery systems. In this phantom study, we verify the capability of a clinical dose planning and delivery system to deliver an F-18-FDG-PET based dose painted treatment plan to a lung tumour. Furthermore, we estimate the uncertainties of the dose painted treatment compared to conventional RT plans. An anthropomorphic thorax phantom of polystyrene and polyurethane was constructed based on CT images of a lung cancer patient. 101 EPR/alanine dosimeters were placed in separate cavities within the phantom. IMRT and VMAT plans were generated in Eclipse (version 10.0, Analytical Anisotropic Algorithm version 10.2.28, Varian Medical Systems, Inc.) for 6 and 15 MV photons, based on F-18-FDG-PET/CT images of the patient. A boost dose of 3.8 Gy/fraction was given to the F-18-FDG-avid region (biological planning volume; BTV), whereas 3.1 Gy/fraction was planned to the planning target volume (PTV, excluding the BTV). For the homogenous plans, 3.2 Gy/fraction was given to the PTV. Irradiation of the phantom was carried out at a Varian Trilogy linear accelerator (Varian Medical Systems, Inc.). Uncertainties involved in treatment planning and delivery were estimated from portal dosimetry gamma evalutation. Measured and calculated doses were compared by Bland-Altmann analysis. For all treatment plans, all dose-volume objectives could be achieved in the treatment planning system. The mean absolute differences between calculated and measured doses were small (
KW - radiotherapy
KW - lung cancer
KW - phantom
KW - IMRT
KW - VMAT
KW - PET
KW - functional imaging
U2 - 10.1088/0031-9155/61/6/2243
DO - 10.1088/0031-9155/61/6/2243
M3 - Article
C2 - 26913997
SN - 0031-9155
VL - 61
SP - 2243
EP - 2254
JO - Physics in Medicine and Biology
JF - Physics in Medicine and Biology
IS - 6
ER -