Impact of daily anatomical changes on EPID-based in vivo dosimetry of VMAT treatments of head-and-neck cancer.

Marcel Van Herk; Roel A Rozendaal; Ben J Mijnheer; Olga Hamming-Vrieze; Anton Mans; Marcel van Herk

doi:10.1016/j.radonc.2015.05.020

Impact of daily anatomical changes on EPID-based in vivo dosimetry of VMAT treatments of head-and-neck cancer.

Marcel Van Herk, Roel A Rozendaal, Ben J Mijnheer, Olga Hamming-Vrieze, Anton Mans, Marcel van Herk

Research output: Contribution to journal › Article › peer-review

Abstract

BACKGROUND AND PURPOSE: Target dose verification for VMAT treatments of head-and-neck (H&N) cancer using 3D in vivo EPID dosimetry is expected to be affected by daily anatomical changes. By including these anatomical changes through cone-beam CT (CBCT) information, the magnitude of this effect is investigated. MATERIALS AND METHODS: For 20 VMAT-treated H&N cancer patients, all plan-CTs (pCTs), 633 CBCTs and 1266 EPID movies were used to compare four dose distributions per fraction: treatment planning system (TPS) calculated dose and EPID reconstructed in vivo dose, both determined using the pCT and using the CBCT. D2, D50 and D98 of the planning target volume (PTV) were determined per dose distribution. RESULTS: When including daily anatomical information, D2, D50 and D98 of the PTV change on average by 0.0±0.4% according to TPS calculations; the standard deviation of the difference between EPID and TPS target dose changes from 2.5% (pCT) to 2.1% (CBCT). Small time trends are seen for both TPS and EPID dose distributions when using the pCT, which disappear when including CBCT information. CONCLUSIONS: Daily anatomical changes hardly influence the target dose distribution for H&N VMAT treatments according to TPS recalculations. Including CBCT information in EPID dose reconstructions slightly improves the agreement with TPS calculations.

Original language	English
Journal	Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology
DOIs	https://doi.org/10.1016/j.radonc.2015.05.020
Publication status	Published - 30 Jun 2015

Keywords

Anatomical changes
EPID dosimetry
In vivo QA

UN SDGs

This output contributes to the following UN Sustainable Development Goals (SDGs)

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10.1016/j.radonc.2015.05.020

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@article{cfebd6711ab4483f91a1e647c7b8c73e,

title = "Impact of daily anatomical changes on EPID-based in vivo dosimetry of VMAT treatments of head-and-neck cancer.",

abstract = "BACKGROUND AND PURPOSE: Target dose verification for VMAT treatments of head-and-neck (H&N) cancer using 3D in vivo EPID dosimetry is expected to be affected by daily anatomical changes. By including these anatomical changes through cone-beam CT (CBCT) information, the magnitude of this effect is investigated. MATERIALS AND METHODS: For 20 VMAT-treated H&N cancer patients, all plan-CTs (pCTs), 633 CBCTs and 1266 EPID movies were used to compare four dose distributions per fraction: treatment planning system (TPS) calculated dose and EPID reconstructed in vivo dose, both determined using the pCT and using the CBCT. D2, D50 and D98 of the planning target volume (PTV) were determined per dose distribution. RESULTS: When including daily anatomical information, D2, D50 and D98 of the PTV change on average by 0.0±0.4% according to TPS calculations; the standard deviation of the difference between EPID and TPS target dose changes from 2.5% (pCT) to 2.1% (CBCT). Small time trends are seen for both TPS and EPID dose distributions when using the pCT, which disappear when including CBCT information. CONCLUSIONS: Daily anatomical changes hardly influence the target dose distribution for H&N VMAT treatments according to TPS recalculations. Including CBCT information in EPID dose reconstructions slightly improves the agreement with TPS calculations.",

keywords = "Anatomical changes, EPID dosimetry, In vivo QA",

author = "{Van Herk}, Marcel and Rozendaal, {Roel A} and Mijnheer, {Ben J} and Olga Hamming-Vrieze and Anton Mans and {van Herk}, Marcel",

year = "2015",

month = jun,

day = "30",

doi = "10.1016/j.radonc.2015.05.020",

language = "English",

journal = "Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology",

issn = "0167-8140",

publisher = "Elsevier BV",

}

TY - JOUR

T1 - Impact of daily anatomical changes on EPID-based in vivo dosimetry of VMAT treatments of head-and-neck cancer.

AU - Van Herk, Marcel

AU - Rozendaal, Roel A

AU - Mijnheer, Ben J

AU - Hamming-Vrieze, Olga

AU - Mans, Anton

AU - van Herk, Marcel

PY - 2015/6/30

Y1 - 2015/6/30

N2 - BACKGROUND AND PURPOSE: Target dose verification for VMAT treatments of head-and-neck (H&N) cancer using 3D in vivo EPID dosimetry is expected to be affected by daily anatomical changes. By including these anatomical changes through cone-beam CT (CBCT) information, the magnitude of this effect is investigated. MATERIALS AND METHODS: For 20 VMAT-treated H&N cancer patients, all plan-CTs (pCTs), 633 CBCTs and 1266 EPID movies were used to compare four dose distributions per fraction: treatment planning system (TPS) calculated dose and EPID reconstructed in vivo dose, both determined using the pCT and using the CBCT. D2, D50 and D98 of the planning target volume (PTV) were determined per dose distribution. RESULTS: When including daily anatomical information, D2, D50 and D98 of the PTV change on average by 0.0±0.4% according to TPS calculations; the standard deviation of the difference between EPID and TPS target dose changes from 2.5% (pCT) to 2.1% (CBCT). Small time trends are seen for both TPS and EPID dose distributions when using the pCT, which disappear when including CBCT information. CONCLUSIONS: Daily anatomical changes hardly influence the target dose distribution for H&N VMAT treatments according to TPS recalculations. Including CBCT information in EPID dose reconstructions slightly improves the agreement with TPS calculations.

AB - BACKGROUND AND PURPOSE: Target dose verification for VMAT treatments of head-and-neck (H&N) cancer using 3D in vivo EPID dosimetry is expected to be affected by daily anatomical changes. By including these anatomical changes through cone-beam CT (CBCT) information, the magnitude of this effect is investigated. MATERIALS AND METHODS: For 20 VMAT-treated H&N cancer patients, all plan-CTs (pCTs), 633 CBCTs and 1266 EPID movies were used to compare four dose distributions per fraction: treatment planning system (TPS) calculated dose and EPID reconstructed in vivo dose, both determined using the pCT and using the CBCT. D2, D50 and D98 of the planning target volume (PTV) were determined per dose distribution. RESULTS: When including daily anatomical information, D2, D50 and D98 of the PTV change on average by 0.0±0.4% according to TPS calculations; the standard deviation of the difference between EPID and TPS target dose changes from 2.5% (pCT) to 2.1% (CBCT). Small time trends are seen for both TPS and EPID dose distributions when using the pCT, which disappear when including CBCT information. CONCLUSIONS: Daily anatomical changes hardly influence the target dose distribution for H&N VMAT treatments according to TPS recalculations. Including CBCT information in EPID dose reconstructions slightly improves the agreement with TPS calculations.

KW - Anatomical changes

KW - EPID dosimetry

KW - In vivo QA

U2 - 10.1016/j.radonc.2015.05.020

DO - 10.1016/j.radonc.2015.05.020

M3 - Article

C2 - 26142267

SN - 0167-8140

JO - Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology

JF - Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology

ER -

Impact of daily anatomical changes on EPID-based in vivo dosimetry of VMAT treatments of head-and-neck cancer.

Abstract

Keywords

UN SDGs

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