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Krayenbuehl J, Di Martino M, Guckenberger M, Andratschke N. Improved plan quality with automated radiotherapy planning for whole brain with hippocampus sparing: a comparison to the RTOG 0933 trial. Radiat Oncol 2017; 12:161. [PMID: 28969706 PMCID: PMC5625717 DOI: 10.1186/s13014-017-0896-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 09/20/2017] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Whole-brain radiation therapy (WBRT) with hippocampus sparing (HS) has been investigated by the radiation oncology working group (RTOG) 0933 trial for patients with multiple brain metastases. They showed a decrease of adverse neurocognitive effects with HS WBRT compared to WBRT alone. With the development of automated treatment planning system (aTPS) in the last years, a standardization of the plan quality at a high level was achieved. The goal of this study was to evaluate the feasibility of using an aTPS for the treatment of HS WBRT and see if the RTOG 0933 dose constraints could be achieved and improved. METHODS Ten consecutive patients treated with HS WBRT were enrolled in this study. 10 × 3 Gy was prescribed according to the RTOG 0933 protocol to 92% of the target volume (whole-brain excluding the hippocampus expanded by 5 mm in 3-dimensions). In contrast to RTOG 0933, the maximum allowed point dose to normal brain was significantly lowered and restricted to 36.5 Gy. All patients were planned with volumetric modulated arc therapy (VMAT) technique using four arcs. Plans were optimized using Auto-Planning (AP) (Philips Radiation Oncology Systems) with one single AP template and optimization. RESULTS All the constraints from the RTOG 0933 trial were achieved. A significant improvement for the maximal dose to 2% of the brain with a reduction of 4 Gy was achieved (33.5 Gy vs. RTOG 37.5 Gy) and the minimum hippocampus dose was reduced by 10% (8.1 Gy vs. RTOG 9 Gy). A steep dose gradient around the hippocampus was achieved with a mean dose of 27.3 Gy at a distance between 0.5 cm and 1 cm from the hippocampus. The effective working time to optimize a plan was kept below 6'. CONCLUSION Automated treatment planning for HS WBRT was able to fulfil all the recommendations from the RTOG 0933 study while significantly improving dose homogeneity and decreasing unnecessary hot spot in the normal brain. With this approach, a standardization of plan quality was achieved and the effective time required for plan optimization was minimized.
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Affiliation(s)
- J. Krayenbuehl
- Department of Radiation Oncology, University Hospital Zurich, Rämistrasse 100, CH-8091 Zurich, Switzerland
| | - M. Di Martino
- Department of Radiation Oncology, University Hospital Zurich, Rämistrasse 100, CH-8091 Zurich, Switzerland
| | - M. Guckenberger
- Department of Radiation Oncology, University Hospital Zurich, Rämistrasse 100, CH-8091 Zurich, Switzerland
| | - N. Andratschke
- Department of Radiation Oncology, University Hospital Zurich, Rämistrasse 100, CH-8091 Zurich, Switzerland
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152
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Abstract
Radiation therapy treatment planning requires an incorporation of uncertainties in order to guarantee an adequate irradiation of the tumor volumes. In current clinical practice, uncertainties are accounted for implicitly with an expansion of the target volume according to generic margin recipes. Alternatively, it is possible to account for uncertainties by explicit minimization of objectives that describe worst-case treatment scenarios, the expectation value of the treatment or the coverage probability of the target volumes during treatment planning. In this note we show that approaches relying on objectives to induce a specific coverage of the clinical target volumes are inevitably sensitive to variation of the relative weighting of the objectives. To address this issue, we introduce coverage-based constraints for intensity-modulated radiation therapy (IMRT) treatment planning. Our implementation follows the concept of coverage-optimized planning that considers explicit error scenarios to calculate and optimize patient-specific probabilities [Formula: see text] of covering a specific target volume fraction [Formula: see text] with a certain dose [Formula: see text]. Using a constraint-based reformulation of coverage-based objectives we eliminate the trade-off between coverage and competing objectives during treatment planning. In-depth convergence tests including 324 treatment plan optimizations demonstrate the reliability of coverage-based constraints for varying levels of probability, dose and volume. General clinical applicability of coverage-based constraints is demonstrated for two cases. A sensitivity analysis regarding penalty variations within this planing study based on IMRT treatment planning using (1) coverage-based constraints, (2) coverage-based objectives, (3) probabilistic optimization, (4) robust optimization and (5) conventional margins illustrates the potential benefit of coverage-based constraints that do not require tedious adjustment of target volume objectives.
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Affiliation(s)
- H Mescher
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center-DKFZ, Im NeuenheimerFeld 280, D-69120 Heidelberg, Germany. Heidelberg Institute for Radiation Oncology-HIRO, Im Neuenheimer Feld 280, D-69120, Germany
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153
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Clarke S, Goodworth J, Westhuyzen J, Chick B, Hoffmann M, Pacey J, Greenham S. Software-based evaluation of a class solution for prostate IMRT planning. Rep Pract Oncol Radiother 2017; 22:441-449. [PMID: 28883765 DOI: 10.1016/j.rpor.2017.08.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Revised: 07/21/2017] [Accepted: 08/02/2017] [Indexed: 11/30/2022] Open
Abstract
AIM To use plan analysis software to evaluate a class solution for prostate intensity modulated radiotherapy (IMRT) planning. BACKGROUND Class solutions for radiotherapy planning are increasingly being considered for streamlining planning. Plan analysis software provides an objective approach to evaluating radiotherapy plans. MATERIALS AND METHODS Three iterations of a class solution for prostate IMRT planning (T1, T2 and Tfinal) were compared to the clinical plan of 74 prostate patients using radiotherapy plan analysis software (Plan IQ™, Sun Nuclear Corporation). A set of institution-specific plan quality metrics (scores) were established, based on best practice guidelines. RESULTS For CTV coverage, Tfinal was not significantly different to the clinical plan. With the exception of 95% PTV coverage, Tfinal metrics were significantly better than the clinical plan for PTV coverage. In the scoring analysis, mean dose, 95% and 107% isodose coverage scores were similar for all the templates and clinical plan. 100% coverage of the CTV clinical plan was similar to Tfinal but scored higher than T1 and T2. There were no significant differences between Tfinal and the clinical plan for the metrics and scores associated with organs at risk. The total plan score was similar for Tfinal and the clinical plan, although the scores for volume receiving total dose outside the PTV were higher for Tfinal than for the clinical plan (P < 0.0001). CONCLUSIONS The radiotherapy plan analysis software was useful for evaluating a class solution for prostate IMRT planning and provided evidence that the class solution produced clinically acceptable plans for these patients.
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Affiliation(s)
- Sarah Clarke
- Department of Radiation Oncology, Mid-North Coast Cancer Institute, Port Macquarie, New South Wales 2444, Australia
| | - Josie Goodworth
- Department of Radiation Oncology, Mid-North Coast Cancer Institute, Coffs Harbour Health Campus, Coffs Harbour, New South Wales 2450, Australia
| | - Justin Westhuyzen
- Department of Radiation Oncology, Mid-North Coast Cancer Institute, Coffs Harbour Health Campus, Coffs Harbour, New South Wales 2450, Australia
| | - Brendan Chick
- Department of Radiation Oncology, Mid-North Coast Cancer Institute, Port Macquarie, New South Wales 2444, Australia
| | - Matthew Hoffmann
- Department of Radiation Oncology, Mid-North Coast Cancer Institute, Port Macquarie, New South Wales 2444, Australia
| | - Jacqueline Pacey
- Department of Radiation Oncology, Mid-North Coast Cancer Institute, Coffs Harbour Health Campus, Coffs Harbour, New South Wales 2450, Australia
| | - Stuart Greenham
- Department of Radiation Oncology, Mid-North Coast Cancer Institute, Coffs Harbour Health Campus, Coffs Harbour, New South Wales 2450, Australia
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154
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Lacornerie T, Rio E, Mahé MA. [Stereotactic body radiation therapy for hepatic malignancies: Organs at risk, uncertainties margins, doses]. Cancer Radiother 2017; 21:574-579. [PMID: 28844506 DOI: 10.1016/j.canrad.2017.07.028] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 07/20/2017] [Accepted: 07/22/2017] [Indexed: 11/30/2022]
Abstract
Stereotactic body radiation therapy for primary and metastatic hepatic malignancies can be performed in association and/or as an alternative to surgery and radiofrequency. The consequences of the great number of techniques available are heterogeneity in contouring, dose prescription and in determination of dose constraints for organs at risk. The objective of this paper is to improve the quality and safety and to help the diffusion of this technique for a majority of patients. In 2016, the French Society of Radiation Oncology (SFRO) published guidelines for external radiotherapy and brachytherapy ("Recorad"). This paper is an update of these recommendations considering recent publications.
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Affiliation(s)
- T Lacornerie
- Service de physique médicale, centre Oscar-Lambret, 3, rue Frédéric-Combemale, 59020 Lille, France.
| | - E Rio
- Service de radiothérapie, institut de cancérologie de l'Ouest René-Gauducheau, boulevard Professeur-Jacques-Monod, 44805 Saint-Herblain, France
| | - M-A Mahé
- Service de radiothérapie, institut de cancérologie de l'Ouest René-Gauducheau, boulevard Professeur-Jacques-Monod, 44805 Saint-Herblain, France
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155
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Speer S, Klein A, Kober L, Weiss A, Yohannes I, Bert C. Automation of radiation treatment planning : Evaluation of head and neck cancer patient plans created by the Pinnacle 3 scripting and Auto-Planning functions. Strahlenther Onkol 2017; 193:656-665. [PMID: 28653120 DOI: 10.1007/s00066-017-1150-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 05/10/2017] [Indexed: 12/25/2022]
Abstract
BACKGROUND Intensity-modulated radiotherapy (IMRT) techniques are now standard practice. IMRT or volumetric-modulated arc therapy (VMAT) allow treatment of the tumor while simultaneously sparing organs at risk. Nevertheless, treatment plan quality still depends on the physicist's individual skills, experiences, and personal preferences. It would therefore be advantageous to automate the planning process. This possibility is offered by the Pinnacle3 treatment planning system (Philips Healthcare, Hamburg, Germany) via its scripting language or Auto-Planning (AP) module. MATERIALS AND METHODS AP module results were compared to in-house scripts and manually optimized treatment plans for standard head and neck cancer plans. Multiple treatment parameters were scored to judge plan quality (100 points = optimum plan). Patients were initially planned manually by different physicists and re-planned using scripts or AP. RESULTS AND DISCUSSION Script-based head and neck plans achieved a mean of 67.0 points and were, on average, superior to manually created (59.1 points) and AP plans (62.3 points). Moreover, they are characterized by reproducibility and lower standard deviation of treatment parameters. Even less experienced staff are able to create at least a good starting point for further optimization in a short time. However, for particular plans, experienced planners perform even better than scripts or AP. Experienced-user input is needed when setting up scripts or AP templates for the first time. Moreover, some minor drawbacks exist, such as the increase of monitor units (+35.5% for scripted plans). CONCLUSION On average, automatically created plans are superior to manually created treatment plans. For particular plans, experienced physicists were able to perform better than scripts or AP; thus, the benefit is greatest when time is short or staff inexperienced.
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Affiliation(s)
- Stefan Speer
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Universitätsstraße 27, 91054, Erlangen, Germany.
| | - Andreas Klein
- EKS Engineering GmbH, Dr.-Mack-Straße 88, 90762, Fürth, Germany
| | - Lukas Kober
- Strahlentherapie Tauber-Franken, Uhlandstraße 7, 97980, Bad Mergentheim, Germany
| | - Alexander Weiss
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Universitätsstraße 27, 91054, Erlangen, Germany
| | - Indra Yohannes
- Rinecker Proton Therapy Center, Schäftlarnstraße 133, 81371, Munich, Germany
| | - Christoph Bert
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Universitätsstraße 27, 91054, Erlangen, Germany
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156
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Individualized Selection of Beam Angles and Treatment Isocenter in Tangential Breast Intensity Modulated Radiation Therapy. Int J Radiat Oncol Biol Phys 2017; 98:447-453. [DOI: 10.1016/j.ijrobp.2017.02.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 01/31/2017] [Accepted: 02/07/2017] [Indexed: 11/22/2022]
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157
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Wieser HP, Cisternas E, Wahl N, Ulrich S, Stadler A, Mescher H, Müller LR, Klinge T, Gabrys H, Burigo L, Mairani A, Ecker S, Ackermann B, Ellerbrock M, Parodi K, Jäkel O, Bangert M. Development of the open-source dose calculation and optimization toolkit matRad. Med Phys 2017; 44:2556-2568. [DOI: 10.1002/mp.12251] [Citation(s) in RCA: 123] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 03/15/2017] [Accepted: 03/17/2017] [Indexed: 11/06/2022] Open
Affiliation(s)
- Hans-Peter Wieser
- Department of Medical Physics in Radiation Oncology; German Cancer Research Center-DKFZ; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
| | - Eduardo Cisternas
- Department of Medical Physics in Radiation Oncology; German Cancer Research Center-DKFZ; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
- Department of Medical Physics in Radiation Oncology; Heidelberg Institute for Radiation Oncology-HIRO; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
| | - Niklas Wahl
- Department of Medical Physics in Radiation Oncology; German Cancer Research Center-DKFZ; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
- Department of Medical Physics in Radiation Oncology; Heidelberg Institute for Radiation Oncology-HIRO; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
| | - Silke Ulrich
- Department of Medical Physics in Radiation Oncology; German Cancer Research Center-DKFZ; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
- Department of Medical Physics in Radiation Oncology; Heidelberg Institute for Radiation Oncology-HIRO; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
| | - Alexander Stadler
- Department of Medical Physics in Radiation Oncology; German Cancer Research Center-DKFZ; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
- Department of Medical Physics in Radiation Oncology; Heidelberg Institute for Radiation Oncology-HIRO; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
| | - Henning Mescher
- Department of Medical Physics in Radiation Oncology; German Cancer Research Center-DKFZ; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
- Department of Medical Physics in Radiation Oncology; Heidelberg Institute for Radiation Oncology-HIRO; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
| | - Lucas-Raphael Müller
- Department of Medical Physics in Radiation Oncology; German Cancer Research Center-DKFZ; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
- Department of Medical Physics in Radiation Oncology; Heidelberg Institute for Radiation Oncology-HIRO; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
| | - Thomas Klinge
- Department of Medical Physics in Radiation Oncology; German Cancer Research Center-DKFZ; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
- Department of Medical Physics in Radiation Oncology; Heidelberg Institute for Radiation Oncology-HIRO; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
| | - Hubert Gabrys
- Department of Medical Physics in Radiation Oncology; German Cancer Research Center-DKFZ; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
- Department of Medical Physics in Radiation Oncology; Heidelberg Institute for Radiation Oncology-HIRO; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
| | - Lucas Burigo
- Department of Medical Physics in Radiation Oncology; German Cancer Research Center-DKFZ; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
- Department of Medical Physics in Radiation Oncology; Heidelberg Institute for Radiation Oncology-HIRO; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
| | - Andrea Mairani
- Department of Medical Physics in Radiation Oncology; Heidelberg Institute for Radiation Oncology-HIRO; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
- Department of Medical Physics in Radiation Oncology; Heidelberg Ion Beam Therapy Center-HIT; Im Neuenheimer Feld 450 D-69120 Heidelberg Germany
| | - Swantje Ecker
- Department of Medical Physics in Radiation Oncology; Heidelberg Institute for Radiation Oncology-HIRO; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
- Department of Medical Physics in Radiation Oncology; Heidelberg Ion Beam Therapy Center-HIT; Im Neuenheimer Feld 450 D-69120 Heidelberg Germany
| | - Benjamin Ackermann
- Department of Medical Physics in Radiation Oncology; Heidelberg Institute for Radiation Oncology-HIRO; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
- Department of Medical Physics in Radiation Oncology; Heidelberg Ion Beam Therapy Center-HIT; Im Neuenheimer Feld 450 D-69120 Heidelberg Germany
| | - Malte Ellerbrock
- Department of Medical Physics in Radiation Oncology; Heidelberg Institute for Radiation Oncology-HIRO; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
- Department of Medical Physics in Radiation Oncology; Heidelberg Ion Beam Therapy Center-HIT; Im Neuenheimer Feld 450 D-69120 Heidelberg Germany
| | - Katia Parodi
- Department of Medical Physics in Radiation Oncology; Heidelberg Institute for Radiation Oncology-HIRO; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
- Department of Medical Physics in Radiation Oncology; Heidelberg Ion Beam Therapy Center-HIT; Im Neuenheimer Feld 450 D-69120 Heidelberg Germany
- Department of Medical Physics in Radiation Oncology; Ludwig-Maximilians-Universität München; Am Coulombwall 1 D-85748 Garching Germany
| | - Oliver Jäkel
- Department of Medical Physics in Radiation Oncology; German Cancer Research Center-DKFZ; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
- Department of Medical Physics in Radiation Oncology; Heidelberg Institute for Radiation Oncology-HIRO; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
- Department of Medical Physics in Radiation Oncology; Heidelberg Ion Beam Therapy Center-HIT; Im Neuenheimer Feld 450 D-69120 Heidelberg Germany
| | - Mark Bangert
- Department of Medical Physics in Radiation Oncology; German Cancer Research Center-DKFZ; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
- Department of Medical Physics in Radiation Oncology; Heidelberg Institute for Radiation Oncology-HIRO; Im Neuenheimer Feld 280 D-69120 Heidelberg Germany
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158
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van Haveren R, Ogryczak W, Verduijn GM, Keijzer M, Heijmen BJM, Breedveld S. Fast and fuzzy multi-objective radiotherapy treatment plan generation for head and neck cancer patients with the lexicographic reference point method (LRPM). Phys Med Biol 2017; 62:4318-4332. [PMID: 28475495 DOI: 10.1088/1361-6560/62/11/4318] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Previously, we have proposed Erasmus-iCycle, an algorithm for fully automated IMRT plan generation based on prioritised (lexicographic) multi-objective optimisation with the 2-phase ϵ-constraint (2pϵc) method. For each patient, the output of Erasmus-iCycle is a clinically favourable, Pareto optimal plan. The 2pϵc method uses a list of objective functions that are consecutively optimised, following a strict, user-defined prioritisation. The novel lexicographic reference point method (LRPM) is capable of solving multi-objective problems in a single optimisation, using a fuzzy prioritisation of the objectives. Trade-offs are made globally, aiming for large favourable gains for lower prioritised objectives at the cost of only slight degradations for higher prioritised objectives, or vice versa. In this study, the LRPM is validated for 15 head and neck cancer patients receiving bilateral neck irradiation. The generated plans using the LRPM are compared with the plans resulting from the 2pϵc method. Both methods were capable of automatically generating clinically relevant treatment plans for all patients. For some patients, the LRPM allowed large favourable gains in some treatment plan objectives at the cost of only small degradations for the others. Moreover, because of the applied single optimisation instead of multiple optimisations, the LRPM reduced the average computation time from 209.2 to 9.5 min, a speed-up factor of 22 relative to the 2pϵc method.
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Affiliation(s)
- Rens van Haveren
- Department of Radiation Oncology, Erasmus MC-Cancer Institute, PO Box 2040, 3000 CA Rotterdam, The Netherlands
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159
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Jagt T, Breedveld S, van de Water S, Heijmen B, Hoogeman M. Near real-time automated dose restoration in IMPT to compensate for daily tissue density variations in prostate cancer. Phys Med Biol 2017; 62:4254-4272. [DOI: 10.1088/1361-6560/aa5c12] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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160
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Fan J, Wang J, Zhang Z, Hu W. Iterative dataset optimization in automated planning: Implementation for breast and rectal cancer radiotherapy. Med Phys 2017; 44:2515-2531. [PMID: 28339103 DOI: 10.1002/mp.12232] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 03/08/2017] [Accepted: 03/13/2017] [Indexed: 11/12/2022] Open
Abstract
PURPOSE To develop a new automated treatment planning solution for breast and rectal cancer radiotherapy. METHODS The automated treatment planning solution developed in this study includes selection of the iterative optimized training dataset, dose volume histogram (DVH) prediction for the organs at risk (OARs), and automatic generation of clinically acceptable treatment plans. The iterative optimized training dataset is selected by an iterative optimization from 40 treatment plans for left-breast and rectal cancer patients who received radiation therapy. A two-dimensional kernel density estimation algorithm (noted as two parameters KDE) which incorporated two predictive features was implemented to produce the predicted DVHs. Finally, 10 additional new left-breast treatment plans are re-planned using the Pinnacle3 Auto-Planning (AP) module (version 9.10, Philips Medical Systems) with the objective functions derived from the predicted DVH curves. Automatically generated re-optimized treatment plans are compared with the original manually optimized plans. RESULTS By combining the iterative optimized training dataset methodology and two parameters KDE prediction algorithm, our proposed automated planning strategy improves the accuracy of the DVH prediction. The automatically generated treatment plans using the dose derived from the predicted DVHs can achieve better dose sparing for some OARs without compromising other metrics of plan quality. CONCLUSIONS The proposed new automated treatment planning solution can be used to efficiently evaluate and improve the quality and consistency of the treatment plans for intensity-modulated breast and rectal cancer radiation therapy.
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Affiliation(s)
- Jiawei Fan
- Department of radiation oncology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Jiazhou Wang
- Department of radiation oncology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Zhen Zhang
- Department of radiation oncology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Weigang Hu
- Department of radiation oncology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
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161
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Breedveld S, Heijmen B. Data for TROTS - The Radiotherapy Optimisation Test Set. Data Brief 2017; 12:143-149. [PMID: 28417100 PMCID: PMC5387893 DOI: 10.1016/j.dib.2017.03.037] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 03/15/2017] [Accepted: 03/28/2017] [Indexed: 11/03/2022] Open
Abstract
The Radiotherapy Optimisation Test Set (TROTS) is an extensive set of problems originating from radiotherapy (radiation therapy) treatment planning. This dataset is created for 2 purposes: (1) to supply a large-scale dense dataset to measure performance and quality of mathematical solvers, and (2) to supply a dataset to investigate the multi-criteria optimisation and decision-making nature of the radiotherapy problem. The dataset contains 120 problems (patients), divided over 6 different treatment protocols/tumour types. Each problem contains numerical data, a configuration for the optimisation problem, and data required to visualise and interpret the results. The data is stored as HDF5 compatible Matlab files, and includes scripts to work with the dataset.
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Affiliation(s)
- Sebastiaan Breedveld
- Erasmus University Medical Center - Cancer Institute, Department of Radiation Oncology, Rotterdam, The Netherlands
| | - Ben Heijmen
- Erasmus University Medical Center - Cancer Institute, Department of Radiation Oncology, Rotterdam, The Netherlands
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162
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Sharfo AWM, Dirkx MLP, Breedveld S, Méndez Romero A, Heijmen BJM. VMAT plus a few computer-optimized non-coplanar IMRT beams (VMAT+) tested for liver SBRT. Radiother Oncol 2017; 123:49-56. [PMID: 28341061 DOI: 10.1016/j.radonc.2017.02.018] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Revised: 02/13/2017] [Accepted: 02/25/2017] [Indexed: 11/29/2022]
Abstract
PURPOSE To propose a novel treatment approach, designated VMAT+, involving addition of <5 IMRT beams with computer-optimized non-coplanar orientations to VMAT, and evaluate it for liver Stereotactic Body Radiation Therapy (SBRT). VMAT+ is investigated as an alternative for (1) coplanar VMAT and (2) multi-beam non-coplanar treatment. METHODS/MATERIALS For fifteen patients with liver metastases, VMAT+ plans were compared with (1) dual-arc VMAT and (2) 25-beam, non-coplanar treatment with computer-optimized beam orientations (25-NCP). All plans were generated fully automatically for delivery of the highest feasible tumor Biologically Effective Dose (BED). OAR doses, intermediate-dose-spillage, dose-compactness, and measured delivery times were evaluated. RESULTS With VMAT+ the maximum achievable tumor BED was equal to that of 25-NCP. Conversely, VMAT resulted in a lower tumor BED in 5 patients. Compared to VMAT, VMAT+ yielded significant dose reductions in OARs. Intermediate-dose-spillage and dose-compactness were significantly improved by 9.8% and 17.3% (p≤0.002), respectively. Treatment times with VMAT+ were only enhanced by 4.1min on average, compared to VMAT (8.4min). Improvements in OAR sparing with 25-NCP, compared to VMAT+, were generally modest and/or statistically insignificant, while delivery times were on average 20.5min longer. CONCLUSIONS For liver SBRT, VMAT+ is equivalent to time-consuming treatment with 25 non-coplanar beams in terms of achievable tumor BED. Compared to VMAT, OAR sparing and intermediate-dose-spillage are significantly improved, with minor increase in delivery time.
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Affiliation(s)
- Abdul Wahab M Sharfo
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands.
| | - Maarten L P Dirkx
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Sebastiaan Breedveld
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | | | - Ben J M Heijmen
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
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163
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Della Gala G, Dirkx MLP, Hoekstra N, Fransen D, Lanconelli N, van de Pol M, Heijmen BJM, Petit SF. Fully automated VMAT treatment planning for advanced-stage NSCLC patients. Strahlenther Onkol 2017; 193:402-409. [PMID: 28314877 PMCID: PMC5405101 DOI: 10.1007/s00066-017-1121-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 03/03/2017] [Indexed: 12/31/2022]
Abstract
PURPOSE To develop a fully automated procedure for multicriterial volumetric modulated arc therapy (VMAT) treatment planning (autoVMAT) for stage III/IV non-small cell lung cancer (NSCLC) patients treated with curative intent. MATERIALS AND METHODS After configuring the developed autoVMAT system for NSCLC, autoVMAT plans were compared with manually generated clinically delivered intensity-modulated radiotherapy (IMRT) plans for 41 patients. AutoVMAT plans were also compared to manually generated VMAT plans in the absence of time pressure. For 16 patients with reduced planning target volume (PTV) dose prescription in the clinical IMRT plan (to avoid violation of organs at risk tolerances), the potential for dose escalation with autoVMAT was explored. RESULTS Two physicians evaluated 35/41 autoVMAT plans (85%) as clinically acceptable. Compared to the manually generated IMRT plans, autoVMAT plans showed statistically significant improved PTV coverage (V95% increased by 1.1% ± 1.1%), higher dose conformity (R50 reduced by 12.2% ± 12.7%), and reduced mean lung, heart, and esophagus doses (reductions of 0.9 Gy ± 1.0 Gy, 1.5 Gy ± 1.8 Gy, 3.6 Gy ± 2.8 Gy, respectively, all p < 0.001). To render the six remaining autoVMAT plans clinically acceptable, a dosimetrist needed less than 10 min hands-on time for fine-tuning. AutoVMAT plans were also considered equivalent or better than manually optimized VMAT plans. For 6/16 patients, autoVMAT allowed tumor dose escalation of 5-10 Gy. CONCLUSION Clinically deliverable, high-quality autoVMAT plans can be generated fully automatically for the vast majority of advanced-stage NSCLC patients. For a subset of patients, autoVMAT allowed for tumor dose escalation.
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Affiliation(s)
- Giuseppe Della Gala
- Department of Radiation Oncology, Erasmus MC Cancer Institute, 5201, 3008 AE, Rotterdam, The Netherlands.,Scuola di Scienze, Alma Mater Studiorum, Università di Bologna, Bologna, Italy
| | - Maarten L P Dirkx
- Department of Radiation Oncology, Erasmus MC Cancer Institute, 5201, 3008 AE, Rotterdam, The Netherlands.
| | - Nienke Hoekstra
- Department of Radiation Oncology, Erasmus MC Cancer Institute, 5201, 3008 AE, Rotterdam, The Netherlands
| | - Dennie Fransen
- Department of Radiation Oncology, Erasmus MC Cancer Institute, 5201, 3008 AE, Rotterdam, The Netherlands
| | - Nico Lanconelli
- Scuola di Scienze, Alma Mater Studiorum, Università di Bologna, Bologna, Italy
| | - Marjan van de Pol
- Department of Radiation Oncology, Erasmus MC Cancer Institute, 5201, 3008 AE, Rotterdam, The Netherlands
| | - Ben J M Heijmen
- Department of Radiation Oncology, Erasmus MC Cancer Institute, 5201, 3008 AE, Rotterdam, The Netherlands
| | - Steven F Petit
- Department of Radiation Oncology, Erasmus MC Cancer Institute, 5201, 3008 AE, Rotterdam, The Netherlands.,Department of Radiation Oncology, Massachusetts General Hospital-Harvard Medical School, Boston, MA, USA
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Buergy D, Sharfo AWM, Heijmen BJM, Voet PWJ, Breedveld S, Wenz F, Lohr F, Stieler F. Fully automated treatment planning of spinal metastases - A comparison to manual planning of Volumetric Modulated Arc Therapy for conventionally fractionated irradiation. Radiat Oncol 2017; 12:33. [PMID: 28143623 PMCID: PMC5282882 DOI: 10.1186/s13014-017-0767-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 01/11/2017] [Indexed: 12/25/2022] Open
Abstract
Background Planning for Volumetric Modulated Arc Therapy (VMAT) may be time consuming and its use is limited by available staff resources. Automated multicriterial treatment planning can eliminate this bottleneck. We compared automatically created (auto) VMAT plans generated by Erasmus-iCycle to manually created VMAT plans for treatment of spinal metastases. Methods Forty-two targets in 32 patients were analyzed. Lungs and kidneys were defined as organs at risk (OARs). Twenty-two patients received radiotherapy on kidney levels, 17 on lung levels, and 3 on both levels. Results All Erasmus-iCycle plans were clinically acceptable. When compared to manual plans, planning target volume (PTV) coverage of auto plans was significantly better. The Homogeneity Index did not differ significantly between the groups. Mean dose to OARs was lower in auto plans concerning both kidneys and the left lung. One hotspot (>110% of D50%) occurred in the spinal cord of one auto plan (33.2 Gy, D50%: 30 Gy). Treatment time was 7% longer in auto plans. Conclusions Erasmus-iCycle plans showed better target coverage and sparing of OARs at the expense of minimally longer treatment times (for which no constraint was set). Electronic supplementary material The online version of this article (doi:10.1186/s13014-017-0767-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Daniel Buergy
- Department of Radiation Oncology, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.
| | - Abdul Wahab M Sharfo
- Department of Radiation Oncology, Erasmus MC-Cancer Institute, Rotterdam, The Netherlands
| | - Ben J M Heijmen
- Department of Radiation Oncology, Erasmus MC-Cancer Institute, Rotterdam, The Netherlands
| | | | - Sebastiaan Breedveld
- Department of Radiation Oncology, Erasmus MC-Cancer Institute, Rotterdam, The Netherlands
| | - Frederik Wenz
- Department of Radiation Oncology, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Frank Lohr
- Department of Radiation Oncology, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Florian Stieler
- Department of Radiation Oncology, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
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165
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Sharfo AWM, Breedveld S, Voet PWJ, Heijkoop ST, Mens JWM, Hoogeman MS, Heijmen BJM. Validation of Fully Automated VMAT Plan Generation for Library-Based Plan-of-the-Day Cervical Cancer Radiotherapy. PLoS One 2016; 11:e0169202. [PMID: 28033342 PMCID: PMC5199117 DOI: 10.1371/journal.pone.0169202] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 12/13/2016] [Indexed: 11/21/2022] Open
Abstract
Purpose To develop and validate fully automated generation of VMAT plan-libraries for plan-of-the-day adaptive radiotherapy in locally-advanced cervical cancer. Material and Methods Our framework for fully automated treatment plan generation (Erasmus-iCycle) was adapted to create dual-arc VMAT treatment plan libraries for cervical cancer patients. For each of 34 patients, automatically generated VMAT plans (autoVMAT) were compared to manually generated, clinically delivered 9-beam IMRT plans (CLINICAL), and to dual-arc VMAT plans generated manually by an expert planner (manVMAT). Furthermore, all plans were benchmarked against 20-beam equi-angular IMRT plans (autoIMRT). For all plans, a PTV coverage of 99.5% by at least 95% of the prescribed dose (46 Gy) had the highest planning priority, followed by minimization of V45Gy for small bowel (SB). Other OARs considered were bladder, rectum, and sigmoid. Results All plans had a highly similar PTV coverage, within the clinical constraints (above). After plan normalizations for exactly equal median PTV doses in corresponding plans, all evaluated OAR parameters in autoVMAT plans were on average lower than in the CLINICAL plans with an average reduction in SB V45Gy of 34.6% (p<0.001). For 41/44 autoVMAT plans, SB V45Gy was lower than for manVMAT (p<0.001, average reduction 30.3%), while SB V15Gy increased by 2.3% (p = 0.011). AutoIMRT reduced SB V45Gy by another 2.7% compared to autoVMAT, while also resulting in a 9.0% reduction in SB V15Gy (p<0.001), but with a prolonged delivery time. Differences between manVMAT and autoVMAT in bladder, rectal and sigmoid doses were ≤ 1%. Improvements in SB dose delivery with autoVMAT instead of manVMAT were higher for empty bladder PTVs compared to full bladder PTVs, due to differences in concavity of the PTVs. Conclusions Quality of automatically generated VMAT plans was superior to manually generated plans. Automatic VMAT plan generation for cervical cancer has been implemented in our clinical routine. Due to the achieved workload reduction, extension of plan libraries has become feasible.
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Affiliation(s)
- Abdul Wahab M. Sharfo
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
- * E-mail:
| | - Sebastiaan Breedveld
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Peter W. J. Voet
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Sabrina T. Heijkoop
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Jan-Willem M. Mens
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Mischa S. Hoogeman
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Ben J. M. Heijmen
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
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166
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Tol JP, Dahele M, Delaney AR, Doornaert P, Slotman BJ, Verbakel WFAR. Detailed evaluation of an automated approach to interactive optimization for volumetric modulated arc therapy plans. Med Phys 2016; 43:1818. [PMID: 27036579 DOI: 10.1118/1.4944063] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
PURPOSE Interactive optimization during treatment planning requires intermittent adjustment of organ-at-risk (OAR) objectives relative to the dose-volume histogram line. This is a labor-intensive process and the resulting plans are prone to variations in quality. The authors' in-house developed approach to automated interactive optimization (AIO) automatically moves the mouse cursor to adjust the position of on-screen optimization objectives. This allows for the use of more objectives per OAR and results in a more frequent and consistent adjustment of these objectives during optimization. The authors report a detailed evaluation of AIO performance in support of its implementation for routine head and neck cancer (HNC) planning and an evaluation for locally advanced lung cancer (LC) planning which requires a different optimization strategy. METHODS Volumetric modulated arc therapy AIO plans (APs) were created for 70 HNC patients with a simultaneously integrated boost and 20 LC patients and benchmarked against their respective manually interactively optimized plans (MPs). The same set of optimization objectives and priorities was used for all APs, although planning target volume (PTV) optimization priorities could be increased manually in a subsequent "continue previous optimization" calculation. HNC plans were benchmarked using mean dose to individual and composite OARs and elective/boost PTV (PTVE/PTVB) volumes receiving 95% and 107% of the prescription dose (V95% and V107%, respectively). A clinician performed blinded comparison of 20 APs and respective MPs. LC plans were compared using PTV V95%/V107%, contralateral lung (CL) volume receiving 5 Gy (V5Gy), total lung (TL)-PTV V5Gy/V20Gy, and esophagus and heart V40Gy/V60Gy/mean doses. RESULTS For HNC, statistically significant improvements in sparing of all OARs, except for the ipsilateral submandibular gland and trachea, were obtained in the APs compared to MPs. Average mean dose to oral cavity, composite salivary, and swallowing structures were 25.4/23.8, 24.2/23.2, and 29.5/25.5 Gy, respectively, for the MPs/APs. PTV heterogeneity was similar: in the APs, PTVB V95% was 0.2% higher while PTV B/PTV E V107% was 0.4%/1.0% lower. In 19 out of 20 HNC patients, the clinician preferred the AP, mainly because of better OAR sparing and PTV dose homogeneity. For LC, APs had a significantly lower CL V5Gy (6.1%), heart mean dose/V60Gy (0.9 Gy/1.2%) and esophagus mean dose/V60Gy (0.9 Gy/2.8%), a nonsignificantly higher TL V20Gy (1.4%), and a slight, but significantly higher dose deposition to the body. PTV dose coverage and homogeneity were similar in the APs and MPs. AIO was considered sufficiently robust for clinical use in LC. CONCLUSIONS HNC and LC APs were at least as good as, and often of improved quality over MPs. To date, AIO has been clinically implemented for HNC planning.
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Affiliation(s)
- Jim P Tol
- Department of Radiation Oncology, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
| | - Max Dahele
- Department of Radiation Oncology, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
| | - Alexander R Delaney
- Department of Radiation Oncology, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
| | - Patricia Doornaert
- Department of Radiation Oncology, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
| | - Ben J Slotman
- Department of Radiation Oncology, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
| | - Wilko F A R Verbakel
- Department of Radiation Oncology, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
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Abstract
PURPOSE Iterative methods for beam angle selection (BAS) for intensity-modulated radiation therapy (IMRT) planning sequentially construct a beneficial ensemble of beam directions. In a naïve implementation, the nth beam is selected by adding beam orientations one-by-one from a discrete set of candidates to an existing ensemble of (n - 1) beams. The best beam orientation is identified in a time consuming process by solving the fluence map optimization (FMO) problem for every candidate beam and selecting the beam that yields the largest improvement to the objective function value. This paper evaluates two alternative methods to accelerate iterative BAS based on surrogates for the FMO objective function value. METHODS We suggest to select candidate beams not based on the FMO objective function value after convergence but (1) based on the objective function value after five FMO iterations of a gradient based algorithm and (2) based on a projected gradient of the FMO problem in the first iteration. The performance of the objective function surrogates is evaluated based on the resulting objective function values and dose statistics in a treatment planning study comprising three intracranial, three pancreas, and three prostate cases. Furthermore, iterative BAS is evaluated for an application in which a small number of noncoplanar beams complement a set of coplanar beam orientations. This scenario is of practical interest as noncoplanar setups may require additional attention of the treatment personnel for every couch rotation. RESULTS Iterative BAS relying on objective function surrogates yields similar results compared to naïve BAS with regard to the objective function values and dose statistics. At the same time, early stopping of the FMO and using the projected gradient during the first iteration enable reductions in computation time by approximately one to two orders of magnitude. With regard to the clinical delivery of noncoplanar IMRT treatments, we could show that optimized beam ensembles using only a few noncoplanar beam orientations often approach the plan quality of fully noncoplanar ensembles. CONCLUSIONS We conclude that iterative BAS in combination with objective function surrogates can be a viable option to implement automated BAS at clinically acceptable computation times.
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Affiliation(s)
- Mark Bangert
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center-DKFZ, Im Neuenheimer Feld 280, Heidelberg D-69120, Germany
| | - Jan Unkelbach
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114
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Winkel D, Bol GH, van Asselen B, Hes J, Scholten V, Kerkmeijer LGW, Raaymakers BW. Development and clinical introduction of automated radiotherapy treatment planning for prostate cancer. Phys Med Biol 2016; 61:8587-8595. [PMID: 27880737 DOI: 10.1088/1361-6560/61/24/8587] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
To develop an automated radiotherapy treatment planning and optimization workflow to efficiently create patient specifically optimized clinical grade treatment plans for prostate cancer and to implement it in clinical practice. A two-phased planning and optimization workflow was developed to automatically generate 77Gy 5-field simultaneously integrated boost intensity modulated radiation therapy (SIB-IMRT) plans for prostate cancer treatment. A retrospective planning study (n = 100) was performed in which automatically and manually generated treatment plans were compared. A clinical pilot (n = 21) was performed to investigate the usability of our method. Operator time for the planning process was reduced to <5 min. The retrospective planning study showed that 98 plans met all clinical constraints. Significant improvements were made in the volume receiving 72Gy (V72Gy) for the bladder and rectum and the mean dose of the bladder and the body. A reduced plan variance was observed. During the clinical pilot 20 automatically generated plans met all constraints and 17 plans were selected for treatment. The automated radiotherapy treatment planning and optimization workflow is capable of efficiently generating patient specifically optimized and improved clinical grade plans. It has now been adopted as the current standard workflow in our clinic to generate treatment plans for prostate cancer.
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Affiliation(s)
- D Winkel
- Department of Radiotherapy, University Medical Center, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
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169
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Wang H, Xing L. Application programming in C# environment with recorded user software interactions and its application in autopilot of VMAT/IMRT treatment planning. J Appl Clin Med Phys 2016; 17:189-203. [PMID: 27929493 PMCID: PMC5690512 DOI: 10.1120/jacmp.v17i6.6425] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Revised: 08/09/2016] [Accepted: 08/08/2016] [Indexed: 11/23/2022] Open
Abstract
An autopilot scheme of volumetric‐modulated arc therapy (VMAT)/intensity‐modulated radiation therapy (IMRT) planning with the guidance of prior knowledge is established with recorded interactions between a planner and a commercial treatment planning system (TPS). Microsoft (MS) Visual Studio Coded UI is applied to record some common planner‐TPS interactions as subroutines. The TPS used in this study is a Windows‐based Eclipse system. The interactions of our application program with Eclipse TPS are realized through a series of subroutines obtained by prerecording the mouse clicks or keyboard strokes of a planner in operating the TPS. A strategy to autopilot Eclipse VMAT/IMRT plan selection process is developed as a specific example of the proposed “scripting” method. The autopiloted planning is navigated by a decision function constructed with a reference plan that has the same prescription and similar anatomy with the case at hand. The calculation proceeds by alternating between the Eclipse optimization and the outer‐loop optimization independent of the Eclipse. In the C# program, the dosimetric characteristics of a reference treatment plan are used to assess and modify the Eclipse planning parameters and to guide the search for a clinically sensible treatment plan. The approach is applied to plan a head and neck (HN) VMAT case and a prostate IMRT case. Our study demonstrated the feasibility of application programming method in C# environment with recorded interactions of planner‐TPS. The process mimics a planner's planning process and automatically provides clinically sensible treatment plans that would otherwise require a large amount of manual trial and error of a planner. The proposed technique enables us to harness a commercial TPS by application programming via the use of recorded human computer interactions and provides an effective tool to greatly facilitate the treatment planning process. PACS number(s): 87.55.D‐, 87.55.kd, 87.55.de
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Affiliation(s)
- Henry Wang
- School of Medicine, Stanford University.
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170
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Heijkoop ST, Westerveld H, Bijker N, Feije R, Sharfo AW, van Wieringen N, Mens JWM, Stalpers LJ, Hoogeman MS. Optimal Patient Positioning (Prone Versus Supine) for VMAT in Gynecologic Cancer: A Dosimetric Study on the Effect of Different Margins. Int J Radiat Oncol Biol Phys 2016; 96:432-439. [DOI: 10.1016/j.ijrobp.2016.05.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 05/13/2016] [Accepted: 05/23/2016] [Indexed: 11/27/2022]
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Rocha H, Dias J, Ventura T, Ferreira B, Lopes MDC. A derivative-free multistart framework for an automated noncoplanar beam angle optimization in IMRT. Med Phys 2016; 43:5514. [DOI: 10.1118/1.4962477] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Yu VY, Tran A, Nguyen D, Cao M, Ruan D, Low DA, Sheng K. The development and verification of a highly accurate collision prediction model for automated noncoplanar plan delivery. Med Phys 2016; 42:6457-67. [PMID: 26520735 DOI: 10.1118/1.4932631] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
PURPOSE Significant dosimetric benefits had been previously demonstrated in highly noncoplanar treatment plans. In this study, the authors developed and verified an individualized collision model for the purpose of delivering highly noncoplanar radiotherapy and tested the feasibility of total delivery automation with Varian TrueBeam developer mode. METHODS A hand-held 3D scanner was used to capture the surfaces of an anthropomorphic phantom and a human subject, which were positioned with a computer-aided design model of a TrueBeam machine to create a detailed virtual geometrical collision model. The collision model included gantry, collimator, and couch motion degrees of freedom. The accuracy of the 3D scanner was validated by scanning a rigid cubical phantom with known dimensions. The collision model was then validated by generating 300 linear accelerator orientations corresponding to 300 gantry-to-couch and gantry-to-phantom distances, and comparing the corresponding distance measurements to their corresponding models. The linear accelerator orientations reflected uniformly sampled noncoplanar beam angles to the head, lung, and prostate. The distance discrepancies between measurements on the physical and virtual systems were used to estimate treatment-site-specific safety buffer distances with 0.1%, 0.01%, and 0.001% probability of collision between the gantry and couch or phantom. Plans containing 20 noncoplanar beams to the brain, lung, and prostate optimized via an in-house noncoplanar radiotherapy platform were converted into XML script for automated delivery and the entire delivery was recorded and timed to demonstrate the feasibility of automated delivery. RESULTS The 3D scanner measured the dimension of the 14 cm cubic phantom within 0.5 mm. The maximal absolute discrepancy between machine and model measurements for gantry-to-couch and gantry-to-phantom was 0.95 and 2.97 cm, respectively. The reduced accuracy of gantry-to-phantom measurements was attributed to phantom setup errors due to the slightly deformable and flexible phantom extremities. The estimated site-specific safety buffer distance with 0.001% probability of collision for (gantry-to-couch, gantry-to-phantom) was (1.23 cm, 3.35 cm), (1.01 cm, 3.99 cm), and (2.19 cm, 5.73 cm) for treatment to the head, lung, and prostate, respectively. Automated delivery to all three treatment sites was completed in 15 min and collision free using a digital Linac. CONCLUSIONS An individualized collision prediction model for the purpose of noncoplanar beam delivery was developed and verified. With the model, the study has demonstrated the feasibility of predicting deliverable beams for an individual patient and then guiding fully automated noncoplanar treatment delivery. This work motivates development of clinical workflows and quality assurance procedures to allow more extensive use and automation of noncoplanar beam geometries.
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Affiliation(s)
- Victoria Y Yu
- Department of Radiation Oncology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California 90024
| | - Angelia Tran
- Department of Radiation Oncology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California 90024
| | - Dan Nguyen
- Department of Radiation Oncology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California 90024
| | - Minsong Cao
- Department of Radiation Oncology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California 90024
| | - Dan Ruan
- Department of Radiation Oncology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California 90024
| | - Daniel A Low
- Department of Radiation Oncology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California 90024
| | - Ke Sheng
- Department of Radiation Oncology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California 90024
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van de Sande MAE, Creutzberg CL, van de Water S, Sharfo AW, Hoogeman MS. Which cervical and endometrial cancer patients will benefit most from intensity-modulated proton therapy? Radiother Oncol 2016; 120:397-403. [PMID: 27452411 DOI: 10.1016/j.radonc.2016.06.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 06/15/2016] [Accepted: 06/29/2016] [Indexed: 10/21/2022]
Abstract
In this dosimetric comparison study it was shown that IMPT with robust planning reduces dose to surrounding organs in cervical and endometrial cancer treatment compared with IMRT. Especially for the para-aortic region, clinically relevant dose reductions were obtained for kidneys, spinal cord and bowel, justifying the use of proton therapy for this indication.
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Affiliation(s)
| | - Carien L Creutzberg
- Department of Radiation Oncology, Leiden University Medical Center, The Netherlands.
| | - Steven van de Water
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Abdul Wahab Sharfo
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Mischa S Hoogeman
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
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Perkó Z, van der Voort SR, van de Water S, Hartman CMH, Hoogeman M, Lathouwers D. Fast and accurate sensitivity analysis of IMPT treatment plans using Polynomial Chaos Expansion. Phys Med Biol 2016; 61:4646-64. [PMID: 27227661 DOI: 10.1088/0031-9155/61/12/4646] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The highly conformal planned dose distribution achievable in intensity modulated proton therapy (IMPT) can severely be compromised by uncertainties in patient setup and proton range. While several robust optimization approaches have been presented to address this issue, appropriate methods to accurately estimate the robustness of treatment plans are still lacking. To fill this gap we present Polynomial Chaos Expansion (PCE) techniques which are easily applicable and create a meta-model of the dose engine by approximating the dose in every voxel with multidimensional polynomials. This Polynomial Chaos (PC) model can be built in an automated fashion relatively cheaply and subsequently it can be used to perform comprehensive robustness analysis. We adapted PC to provide among others the expected dose, the dose variance, accurate probability distribution of dose-volume histogram (DVH) metrics (e.g. minimum tumor or maximum organ dose), exact bandwidths of DVHs, and to separate the effects of random and systematic errors. We present the outcome of our verification experiments based on 6 head-and-neck (HN) patients, and exemplify the usefulness of PCE by comparing a robust and a non-robust treatment plan for a selected HN case. The results suggest that PCE is highly valuable for both research and clinical applications.
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Affiliation(s)
- Zoltán Perkó
- Department of Radiation, Science and Technology, Delft University of Technology, Section Nuclear Energy and Radiation Applications, Mekelweg 15, Delft, The Netherlands
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Wang Y, Breedveld S, Heijmen B, Petit SF. Evaluation of plan quality assurance models for prostate cancer patients based on fully automatically generated Pareto-optimal treatment plans. Phys Med Biol 2016; 61:4268-82. [PMID: 27203748 DOI: 10.1088/0031-9155/61/11/4268] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
IMRT planning with commercial Treatment Planning Systems (TPSs) is a trial-and-error process. Consequently, the quality of treatment plans may not be consistent among patients, planners and institutions. Recently, different plan quality assurance (QA) models have been proposed, that could flag and guide improvement of suboptimal treatment plans. However, the performance of these models was validated using plans that were created using the conventional trail-and-error treatment planning process. Consequently, it is challenging to assess and compare quantitatively the accuracy of different treatment planning QA models. Therefore, we created a golden standard dataset of consistently planned Pareto-optimal IMRT plans for 115 prostate patients. Next, the dataset was used to assess the performance of a treatment planning QA model that uses the overlap volume histogram (OVH). 115 prostate IMRT plans were fully automatically planned using our in-house developed TPS Erasmus-iCycle. An existing OVH model was trained on the plans of 58 of the patients. Next it was applied to predict DVHs of the rectum, bladder and anus of the remaining 57 patients. The predictions were compared with the achieved values of the golden standard plans for the rectum D mean, V 65, and V 75, and D mean of the anus and the bladder. For the rectum, the prediction errors (predicted-achieved) were only -0.2 ± 0.9 Gy (mean ± 1 SD) for D mean,-1.0 ± 1.6% for V 65, and -0.4 ± 1.1% for V 75. For D mean of the anus and the bladder, the prediction error was 0.1 ± 1.6 Gy and 4.8 ± 4.1 Gy, respectively. Increasing the training cohort to 114 patients only led to minor improvements. A dataset of consistently planned Pareto-optimal prostate IMRT plans was generated. This dataset can be used to train new, and validate and compare existing treatment planning QA models, and has been made publicly available. The OVH model was highly accurate in predicting rectum and anus DVHs. For the bladder, larger prediction errors were observed.
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Affiliation(s)
- Yibing Wang
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
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176
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van de Water S, van Dam I, Schaart DR, Al-Mamgani A, Heijmen BJM, Hoogeman MS. The price of robustness; impact of worst-case optimization on organ-at-risk dose and complication probability in intensity-modulated proton therapy for oropharyngeal cancer patients. Radiother Oncol 2016; 120:56-62. [PMID: 27178142 DOI: 10.1016/j.radonc.2016.04.038] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 03/24/2016] [Accepted: 04/21/2016] [Indexed: 01/08/2023]
Abstract
PURPOSE To quantify the impact of the degree of robustness against setup errors and range errors on organ-at-risk (OAR) dose and normal tissue complication probabilities (NTCPs) in intensity-modulated proton therapy for oropharyngeal cancer patients. MATERIAL AND METHODS For 20 oropharyngeal cases (10 unilateral and 10 bilateral), robust treatment plans were generated using 'minimax' worst-case optimization. We varied the robustness against setup errors ('setup robustness') from 1 to 7mm and the robustness against range errors ('range robustness') from 1% to 7% (+1mm). We evaluated OAR doses and NTCP-values for xerostomia, dysphagia and larynx edema. RESULTS Varying the degree of setup robustness was found to have a considerably larger impact than varying the range robustness. Increasing setup robustness from 1mm to 3, 5, and 7mm resulted in average NTCP-values to increase by 1.9, 4.4 and 7.5 percentage point, whereas they increased by only 0.4, 0.8 and 1.2 percentage point when increasing range robustness from 1% to 3%, 5% and 7%. The degree of setup robustness was observed to have a clinically significant impact in bilateral cases in particular. CONCLUSIONS For oropharyngeal cancer patients, minimizing setup errors should be given a higher priority than minimizing range errors.
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Affiliation(s)
- Steven van de Water
- Erasmus MC Cancer Institute, Department of Radiation Oncology, Rotterdam, The Netherlands.
| | - Iris van Dam
- Erasmus MC Cancer Institute, Department of Radiation Oncology, Rotterdam, The Netherlands; Delft University of Technology, Faculty of Applied Sciences, Section Radiation Detection and Medical Imaging, The Netherlands
| | - Dennis R Schaart
- Delft University of Technology, Faculty of Applied Sciences, Section Radiation Detection and Medical Imaging, The Netherlands
| | - Abrahim Al-Mamgani
- Erasmus MC Cancer Institute, Department of Radiation Oncology, Rotterdam, The Netherlands
| | - Ben J M Heijmen
- Erasmus MC Cancer Institute, Department of Radiation Oncology, Rotterdam, The Netherlands
| | - Mischa S Hoogeman
- Erasmus MC Cancer Institute, Department of Radiation Oncology, Rotterdam, The Netherlands
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177
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van der Voort S, van de Water S, Perkó Z, Heijmen B, Lathouwers D, Hoogeman M. Robustness Recipes for Minimax Robust Optimization in Intensity Modulated Proton Therapy for Oropharyngeal Cancer Patients. Int J Radiat Oncol Biol Phys 2016; 95:163-170. [DOI: 10.1016/j.ijrobp.2016.02.035] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 02/08/2016] [Accepted: 02/09/2016] [Indexed: 11/15/2022]
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178
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Tol JP, Doornaert P, Witte BI, Dahele M, Slotman BJ, Verbakel WFAR. A longitudinal evaluation of improvements in radiotherapy treatment plan quality for head and neck cancer patients. Radiother Oncol 2016; 119:337-43. [PMID: 27130730 DOI: 10.1016/j.radonc.2016.04.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 04/08/2016] [Accepted: 04/08/2016] [Indexed: 10/21/2022]
Abstract
PURPOSE To investigate changes in head-and-neck cancer (HNC) plan quality following the introduction of new technologies and planning techniques in the last decade. METHODS AND MATERIALS Thirty plans were selected from each of four successive periods (P). P1: 7-field static intensity-modulated radiotherapy (IMRT) with parotid gland sparing; P2: dual-arc volumetric-modulated arc therapy (VMAT, similar to P3-P4), including submandibular gland sparing; P3: inclusion of individual swallowing muscles and attempts to further reduce parotid and oral cavity doses through manual interactive optimization; P4: containing the same organs-at-risk (OARs) as P3, but automatically interactively optimized. Plan benchmarking included mean salivary gland/swallowing muscle/oral cavity (Dsal/Dswal/Doc) doses. Differences in mean doses between the periods were analyzed by an ANCOVA, taking geometric differences across periods into account. RESULTS Compared to P1, P2 plans improved Dsal by 3.4Gy on average. P3 improved Dsal/Dswal/Doc by 6.9/11.5/7.2Gy over P2, showing that Dswal and Dsal could be improved simultaneously. In P4, Doc/Dswal slightly improved over P3 by 1.7/3.8Gy. Improved OAR sparing in P3/P4 did not come at the cost of increased dose deposition elsewhere and planning target volume (PTV) dose homogeneity was similar. CONCLUSIONS New technologies and planning techniques were successfully implemented into routine clinical care and resulting in improved HNC plan quality.
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Affiliation(s)
- Jim P Tol
- Department of Radiation Oncology, VU University Medical Center, Amsterdam, The Netherlands.
| | - Patricia Doornaert
- Department of Radiation Oncology, VU University Medical Center, Amsterdam, The Netherlands
| | - Birgit I Witte
- Department of Epidemiology and Biostatistics, VU University Medical Center, Amsterdam, The Netherlands
| | - Max Dahele
- Department of Radiation Oncology, VU University Medical Center, Amsterdam, The Netherlands
| | - Ben J Slotman
- Department of Radiation Oncology, VU University Medical Center, Amsterdam, The Netherlands
| | - Wilko F A R Verbakel
- Department of Radiation Oncology, VU University Medical Center, Amsterdam, The Netherlands
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Fully automatic volumetric modulated arc therapy plan generation for rectal cancer. Radiother Oncol 2016; 119:531-6. [PMID: 27131593 DOI: 10.1016/j.radonc.2016.04.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 04/06/2016] [Accepted: 04/08/2016] [Indexed: 02/05/2023]
Abstract
BACKGROUND AND PURPOSE To develop and evaluate a fully automatic rectal planning optimizer (ARPO) for volumetric modulated arc therapy (VMAT) treatment planning without human interaction. MATERIALS AND METHODS The ARPO was developed using inherent Pinnacle(3) script language; it was designed to perform the whole planning process including planning structure generation, beam placement, doseline setting and treatment planning. The automatic scheme adjusts the objectives of the objective function simulating the operation of dosimetrists based on our clinical experience. A total of 29 planned rectal cancer patients were retrospectively replanned using the ARPO (VMATauto) under the same constraints. RESULTS With the ARPO, the hands-on time required for the whole planning process was significantly reduced to <1min. All VMATauto plans were recognized as clinically acceptable and 69% as clinically improved; 3% of VMATauto plans were marked equal and 28% inferior to manually generated VMATman plans when reviewed in a single-blind study by one experienced radiation oncologist. Without any planning workload the VMATauto plans had similar planning target volume dose coverage to the VMATman plans and statistically better organ-at-risk sparing, especially regarding lower small intestine irradiation. CONCLUSIONS The ARPO is robust and dramatically efficient in clinical application and provides improved planning quality.
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180
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van de Schoot AJAJ, Visser J, van Kesteren Z, Janssen TM, Rasch CRN, Bel A. Beam configuration selection for robust intensity-modulated proton therapy in cervical cancer using Pareto front comparison. Phys Med Biol 2016; 61:1780-94. [PMID: 26854384 DOI: 10.1088/0031-9155/61/4/1780] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The Pareto front reflects the optimal trade-offs between conflicting objectives and can be used to quantify the effect of different beam configurations on plan robustness and dose-volume histogram parameters. Therefore, our aim was to develop and implement a method to automatically approach the Pareto front in robust intensity-modulated proton therapy (IMPT) planning. Additionally, clinically relevant Pareto fronts based on different beam configurations will be derived and compared to enable beam configuration selection in cervical cancer proton therapy. A method to iteratively approach the Pareto front by automatically generating robustly optimized IMPT plans was developed. To verify plan quality, IMPT plans were evaluated on robustness by simulating range and position errors and recalculating the dose. For five retrospectively selected cervical cancer patients, this method was applied for IMPT plans with three different beam configurations using two, three and four beams. 3D Pareto fronts were optimized on target coverage (CTV D(99%)) and OAR doses (rectum V30Gy; bladder V40Gy). Per patient, proportions of non-approved IMPT plans were determined and differences between patient-specific Pareto fronts were quantified in terms of CTV D(99%), rectum V(30Gy) and bladder V(40Gy) to perform beam configuration selection. Per patient and beam configuration, Pareto fronts were successfully sampled based on 200 IMPT plans of which on average 29% were non-approved plans. In all patients, IMPT plans based on the 2-beam set-up were completely dominated by plans with the 3-beam and 4-beam configuration. Compared to the 3-beam set-up, the 4-beam set-up increased the median CTV D(99%) on average by 0.2 Gy and decreased the median rectum V(30Gy) and median bladder V(40Gy) on average by 3.6% and 1.3%, respectively. This study demonstrates a method to automatically derive Pareto fronts in robust IMPT planning. For all patients, the defined four-beam configuration was found optimal in terms of plan robustness, target coverage and OAR sparing.
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Affiliation(s)
- A J A J van de Schoot
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
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181
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Dias J, Rocha H, Ventura T, Ferreira B, Lopes MDC. Automated fluence map optimization based on fuzzy inference systems. Med Phys 2016; 43:1083-95. [DOI: 10.1118/1.4941007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Affiliation(s)
- Joana Dias
- FEUC and Inesc‐Coimbra, University of Coimbra, Coimbra 3004512, Portugal
| | - Humberto Rocha
- Inesc‐Coimbra, University of Coimbra, Coimbra 3000033, Portugal
| | - Tiago Ventura
- Medical Physics Department, IPOCFG, EPE, Coimbra, Coimbra 3000075, Portugal and Physics Department, University of Aveiro, Aveiro 3810193, Portugal
| | - Brígida Ferreira
- School of Allied Health Technologies Polytechnic Institute of Porto, Vila Nova de Gaia, 4400330 and I3N Department of Physics, Aveiro University, Aveiro 3810193 Portugal
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Amit G, Purdie TG, Levinshtein A, Hope AJ, Lindsay P, Marshall A, Jaffray DA, Pekar V. Automatic learning-based beam angle selection for thoracic IMRT. Med Phys 2015; 42:1992-2005. [PMID: 25832090 DOI: 10.1118/1.4908000] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE The treatment of thoracic cancer using external beam radiation requires an optimal selection of the radiation beam directions to ensure effective coverage of the target volume and to avoid unnecessary treatment of normal healthy tissues. Intensity modulated radiation therapy (IMRT) planning is a lengthy process, which requires the planner to iterate between choosing beam angles, specifying dose-volume objectives and executing IMRT optimization. In thorax treatment planning, where there are no class solutions for beam placement, beam angle selection is performed manually, based on the planner's clinical experience. The purpose of this work is to propose and study a computationally efficient framework that utilizes machine learning to automatically select treatment beam angles. Such a framework may be helpful for reducing the overall planning workload. METHODS The authors introduce an automated beam selection method, based on learning the relationships between beam angles and anatomical features. Using a large set of clinically approved IMRT plans, a random forest regression algorithm is trained to map a multitude of anatomical features into an individual beam score. An optimization scheme is then built to select and adjust the beam angles, considering the learned interbeam dependencies. The validity and quality of the automatically selected beams evaluated using the manually selected beams from the corresponding clinical plans as the ground truth. RESULTS The analysis included 149 clinically approved thoracic IMRT plans. For a randomly selected test subset of 27 plans, IMRT plans were generated using automatically selected beams and compared to the clinical plans. The comparison of the predicted and the clinical beam angles demonstrated a good average correspondence between the two (angular distance 16.8° ± 10°, correlation 0.75 ± 0.2). The dose distributions of the semiautomatic and clinical plans were equivalent in terms of primary target volume coverage and organ at risk sparing and were superior over plans produced with fixed sets of common beam angles. The great majority of the automatic plans (93%) were approved as clinically acceptable by three radiation therapy specialists. CONCLUSIONS The results demonstrated the feasibility of utilizing a learning-based approach for automatic selection of beam angles in thoracic IMRT planning. The proposed method may assist in reducing the manual planning workload, while sustaining plan quality.
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Affiliation(s)
- Guy Amit
- Radiation Medicine Program, Princess Margaret Cancer Centre, Toronto, Ontario M5G 2M9, Canada
| | - Thomas G Purdie
- Radiation Medicine Program, Princess Margaret Cancer Centre, Toronto, Ontario M5G 2M9, Canada; Department of Radiation Oncology, University of Toronto, Toronto, Ontario M5S 3E2, Canada; and Techna Institute, University Health Network, Toronto, Ontario M5G 1P5, Canada
| | - Alex Levinshtein
- Department of Computer Science, University of Toronto, Toronto, Ontario M5S 3G4, Canada
| | - Andrew J Hope
- Radiation Medicine Program, Princess Margaret Cancer Centre, Toronto, Ontario M5G 2M9, Canada and Department of Radiation Oncology, University of Toronto, Toronto, Ontario M5S 3E2, Canada
| | - Patricia Lindsay
- Radiation Medicine Program, Princess Margaret Cancer Centre, Toronto, Ontario M5G 2M9, Canada and Department of Radiation Oncology, University of Toronto, Toronto, Ontario M5S 3E2, Canada
| | - Andrea Marshall
- Radiation Medicine Program, Princess Margaret Cancer Centre, Toronto, Ontario M5G 2M9, Canada
| | - David A Jaffray
- Radiation Medicine Program, Princess Margaret Cancer Centre, Toronto, Ontario M5G 2M9, Canada; Department of Radiation Oncology, University of Toronto, Toronto, Ontario M5S 3E2, Canada; and Techna Institute, University Health Network, Toronto, Ontario M5G 1P5, Canada
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183
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Petit SF, van Elmpt W. Accurate prediction of target dose-escalation and organ-at-risk dose levels for non-small cell lung cancer patients. Radiother Oncol 2015; 117:453-8. [DOI: 10.1016/j.radonc.2015.07.040] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Revised: 06/05/2015] [Accepted: 07/25/2015] [Indexed: 10/23/2022]
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Can knowledge-based DVH predictions be used for automated, individualized quality assurance of radiotherapy treatment plans? Radiat Oncol 2015; 10:234. [PMID: 26584574 PMCID: PMC4653923 DOI: 10.1186/s13014-015-0542-1] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 11/11/2015] [Indexed: 11/18/2022] Open
Abstract
Background Treatment plan quality assurance (QA) is important for clinical studies and for institutions aiming to generate near-optimal individualized treatment plans. However, determining how good a given plan is for that particular patient (individualized patient/plan QA, in contrast to running through a checklist of generic QA parameters applied to all patients) is difficult, time consuming and operator-dependent. We therefore evaluated the potential of RapidPlan, a commercial knowledge-based planning solution, to automate this process, by predicting achievable OAR doses for individual patients based on a model library consisting of historical plans with a range of organ-at-risk (OAR) to planning target volume (PTV) geometries and dosimetries. Methods A 90-plan RapidPlan model, generated using previously created automatic interactively optimized (AIO) plans, was used to predict achievable OAR dose-volume histograms (DVHs) for the parotid glands, submandibular glands, individual swallowing muscles and oral cavities of 20 head and neck cancer (HNC) patients using a volumetric modulated (RapidArc) simultaneous integrated boost technique. Predicted mean OAR doses were compared with mean doses achieved when RapidPlan was used to make a new plan. Differences between the achieved and predicted DVH-lines were analyzed. Finally, RapidPlan predictions were used to evaluate achieved OAR sparing of AIO and manual interactively optimized plans. Results For all OARs, strong linear correlations (R2 = 0.94–0.99) were found between predicted and achieved mean doses. RapidPlan generally overestimated the amount of achievable sparing for OARs with a large degree of OAR-PTV overlap. RapidPlan QA using predicted doses alone identified that for 50 % (10/20) of the manually optimized plans, sparing of the composite salivary glands, oral cavity or composite swallowing muscles could be improved by at least 3 Gy, 5 Gy or 7 Gy, respectively, while this was the case for 20 % (4/20) AIO plans. These predicted gains were validated by replanning the identified patients using RapidPlan. Conclusions Strong correlations between predicted and achieved mean doses indicate that RapidPlan could accurately predict achievable mean doses. This shows the feasibility of using RapidPlan DVH prediction alone for automated individualized head and neck plan QA. This has applications in individual centers and clinical trials.
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Fogliata A, Nicolini G, Clivio A, Vanetti E, Laksar S, Tozzi A, Scorsetti M, Cozzi L. A broad scope knowledge based model for optimization of VMAT in esophageal cancer: validation and assessment of plan quality among different treatment centers. Radiat Oncol 2015; 10:220. [PMID: 26521015 PMCID: PMC4628288 DOI: 10.1186/s13014-015-0530-5] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2015] [Accepted: 10/26/2015] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND To evaluate the performance of a broad scope model-based optimisation process for volumetric modulated arc therapy applied to esophageal cancer. METHODS AND MATERIALS A set of 70 previously treated patients in two different institutions, were selected to train a model for the prediction of dose-volume constraints. The model was built with a broad-scope purpose, aiming to be effective for different dose prescriptions and tumour localisations. It was validated on three groups of patients from the same institution and from another clinic not providing patients for the training phase. Comparison of the automated plans was done against reference cases given by the clinically accepted plans. RESULTS Quantitative improvements (statistically significant for the majority of the analysed dose-volume parameters) were observed between the benchmark and the test plans. Of 624 dose-volume objectives assessed for plan evaluation, in 21 cases (3.3 %) the reference plans failed to respect the constraints while the model-based plans succeeded. Only in 3 cases (<0.5 %) the reference plans passed the criteria while the model-based failed. In 5.3 % of the cases both groups of plans failed and in the remaining cases both passed the tests. CONCLUSIONS Plans were optimised using a broad scope knowledge-based model to determine the dose-volume constraints. The results showed dosimetric improvements when compared to the benchmark data. Particularly the plans optimised for patients from the third centre, not participating to the training, resulted in superior quality. The data suggests that the new engine is reliable and could encourage its application to clinical practice.
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Affiliation(s)
- Antonella Fogliata
- Radiotherapy and Radiosurgery Department, Humanitas Clinical and Research Center, Milan-Rozzano, Italy
| | - Giorgia Nicolini
- Oncology Institute of Southern Switzerland, Bellinzona, Switzerland
| | | | - Eugenio Vanetti
- Oncology Institute of Southern Switzerland, Bellinzona, Switzerland
| | - Sarbani Laksar
- Radiotherapy Department, Tata Memorial Hospital, Mumbai, India
| | - Angelo Tozzi
- Radiotherapy and Radiosurgery Department, Humanitas Clinical and Research Center, Milan-Rozzano, Italy
| | - Marta Scorsetti
- Radiotherapy and Radiosurgery Department, Humanitas Clinical and Research Center, Milan-Rozzano, Italy
| | - Luca Cozzi
- Radiotherapy and Radiosurgery Department, Humanitas Clinical and Research Center, Milan-Rozzano, Italy.
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Bratengeier K, Holubyev K. Characteristics of non-coplanar IMRT in the presence of target-embedded organs at risk. Radiat Oncol 2015; 10:207. [PMID: 26458947 PMCID: PMC5480416 DOI: 10.1186/s13014-015-0494-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Accepted: 09/03/2015] [Indexed: 11/23/2022] Open
Abstract
Background The aim is to analyze characteristics and to study the potentials of non-coplanar intensity modulated radiation therapy (IMRT) techniques. The planning study applies to generalized organ at risk (OAR) – planning target volume (PTV) geometries. Methods The authors focus on OARs embedded in the PTV. The OAR shapes are spherically symmetric (A), cylindrical (B), and bended (C). Several IMRT techniques are used for the planning study: a) non-coplanar quasi-isotropic; b) two sets of equidistant coplanar beams, half of beams incident in a plane perpendicular to the principal plane; c) coplanar equidistant (reference); d) coplanar plus one orthogonal beam. The number of beam directions varies from 9 to 16. The orientation of the beam sets is systematically changed; dose distributions resulting from optimal fluence are explored. A selection of plans is optimized with direct machine parameter optimization (DMPO) allowing 120 and 64 segments. The overall plan quality, PTV coverage, and OAR sparing are evaluated. Results For all fluence based techniques in cases A and C, plan quality increased considerably if more irradiation directions were used. For the cylindrically symmetric case B, however, only a weak beam number dependence was observed for the best beam set orientation, for which non-coplanar directions could be found where OAR- and PTV-projections did not overlap. IMRT plans using quasi-isotropical distributed non-coplanar beams showed stable results for all topologies A, B, C, as long as 16 beams were chosen; also the most unfavorable beam arrangement created results of similar quality as the optimally oriented coplanar configuration. For smaller number of beams or application in the trunk, a coplanar technique with additional orthogonal beam could be recommended. Techniques using 120 segments created by DMPO could qualitatively reproduce the fluence based results. However, for a reduced number of segments the beam number dependence declined or even reversed for the used planning system and the plan quality degraded substantially. Conclusions Topologies with targets encompassing sensitive OAR require sufficient number of beams of 15 or more. For the subgroup of topologies where beam incidences are possible which cover the whole PTV without direct OAR irradiation, the quality dependence on the number of beams is much less pronounced above 9 beams. However, these special non-coplanar beam directions have to be found. On the basis of this work the non-coplanar IMRT techniques can be chosen for further clinical planning studies. Electronic supplementary material The online version of this article (doi:10.1186/s13014-015-0494-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Klaus Bratengeier
- Department of Radiation Oncology, University of Würzburg, Josef-Schneider-Str. 11, 97080, Würzburg, Germany.
| | - Kostyantyn Holubyev
- Department of Radiation Oncology, University of Würzburg, Josef-Schneider-Str. 11, 97080, Würzburg, Germany
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Lafond C, Simon A, Henry O, Périchon N, Castelli J, Acosta O, de Crevoisier R. Radiothérapie adaptative en routine ? État de l’art : point de vue du physicien médical. Cancer Radiother 2015; 19:450-7. [DOI: 10.1016/j.canrad.2015.06.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 06/01/2015] [Indexed: 12/22/2022]
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188
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Sheng K, Shepard DM, Orton CG. Point/Counterpoint. Noncoplanar beams improve dosimetry quality for extracranial intensity modulated radiotherapy and should be used more extensively. Med Phys 2015; 42:531-3. [PMID: 25652473 DOI: 10.1118/1.4895981] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Affiliation(s)
- Ke Sheng
- Radiation Oncology, David Geffen School of Medicine at UCLA, Los Angeles, California 90095 (Tel: 310-983-3146; E-mail: )
| | - David M Shepard
- Medical Physics, Swedish Cancer Institute, Seattle, Washington 98104 (Tel: 206-215-3306; E-mail: )
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Wild E, Bangert M, Nill S, Oelfke U. Noncoplanar VMAT for nasopharyngeal tumors: Plan quality versus treatment time. Med Phys 2015; 42:2157-68. [PMID: 25979010 DOI: 10.1118/1.4914863] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
PURPOSE The authors investigated the potential of optimized noncoplanar irradiation trajectories for volumetric modulated arc therapy (VMAT) treatments of nasopharyngeal patients and studied the trade-off between treatment plan quality and delivery time in radiation therapy. METHODS For three nasopharyngeal patients, the authors generated treatment plans for nine different delivery scenarios using dedicated optimization methods. They compared these scenarios according to dose characteristics, number of beam directions, and estimated delivery times. In particular, the authors generated the following treatment plans: (1) a 4π plan, which is a not sequenced, fluence optimized plan that uses beam directions from approximately 1400 noncoplanar directions and marks a theoretical upper limit of the treatment plan quality, (2) a coplanar 2π plan with 72 coplanar beam directions as pendant to the noncoplanar 4π plan, (3) a coplanar VMAT plan, (4) a coplanar step and shoot (SnS) plan, (5) a beam angle optimized (BAO) coplanar SnS IMRT plan, (6) a noncoplanar BAO SnS plan, (7) a VMAT plan with rotated treatment couch, (8) a noncoplanar VMAT plan with an optimized great circle around the patient, and (9) a noncoplanar BAO VMAT plan with an arbitrary trajectory around the patient. RESULTS VMAT using optimized noncoplanar irradiation trajectories reduced the mean and maximum doses in organs at risk compared to coplanar VMAT plans by 19% on average while the target coverage remains constant. A coplanar BAO SnS plan was superior to coplanar SnS or VMAT; however, noncoplanar plans like a noncoplanar BAO SnS plan or noncoplanar VMAT yielded a better plan quality than the best coplanar 2π plan. The treatment plan quality of VMAT plans depended on the length of the trajectory. The delivery times of noncoplanar VMAT plans were estimated to be 6.5 min in average; 1.6 min longer than a coplanar plan but on average 2.8 min faster than a noncoplanar SnS plan with comparable treatment plan quality. CONCLUSIONS The authors' study reconfirms the dosimetric benefits of noncoplanar irradiation of nasopharyngeal tumors. Both SnS using optimized noncoplanar beam ensembles and VMAT using an optimized, arbitrary, noncoplanar trajectory enabled dose reductions in organs at risk compared to coplanar SnS and VMAT. Using great circles or simple couch rotations to implement noncoplanar VMAT, however, was not sufficient to yield meaningful improvements in treatment plan quality. The authors estimate that noncoplanar VMAT using arbitrary optimized irradiation trajectories comes at an increased delivery time compared to coplanar VMAT yet at a decreased delivery time compared to noncoplanar SnS IMRT.
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Affiliation(s)
- Esther Wild
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center, Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany
| | - Mark Bangert
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center, Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany
| | - Simeon Nill
- Joint Department of Physics at The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London SM2 5NG, United Kingdom
| | - Uwe Oelfke
- Joint Department of Physics at The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London SM2 5NG, United Kingdom and Department of Medical Physics in Radiation Oncology, German Cancer Research Center, Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany
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190
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Tol JP, Dahele M, Peltola J, Nord J, Slotman BJ, Verbakel WFAR. Automatic interactive optimization for volumetric modulated arc therapy planning. Radiat Oncol 2015; 10:75. [PMID: 25885689 PMCID: PMC4394415 DOI: 10.1186/s13014-015-0388-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Accepted: 03/25/2015] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND Intensity modulated radiotherapy treatment planning for sites with many different organs-at-risk (OAR) is complex and labor-intensive, making it hard to obtain consistent plan quality. With the aim of addressing this, we developed a program (automatic interactive optimizer, AIO) designed to automate the manual interactive process for the Eclipse treatment planning system. We describe AIO and present initial evaluation data. METHODS Our current institutional volumetric modulated arc therapy (RapidArc) planning approach for head and neck tumors places 3-4 adjustable OAR optimization objectives along the dose-volume histogram (DVH) curve that is displayed in the optimization window. AIO scans this window and uses color-coding to differentiate between the DVH-lines, allowing it to automatically adjust the location of the optimization objectives frequently and in a more consistent fashion. We compared RapidArc AIO plans (using 9 optimization objectives per OAR) with the clinical plans of 10 patients, and evaluated optimal AIO settings. AIO consistency was tested by replanning a single patient 5 times. RESULTS Average V95&V107 of the boost planning target volume (PTV) and V95 of the elective PTV differed by ≤0.5%, while average elective PTV V107 improved by 1.5%. Averaged over all patients, AIO reduced mean doses to individual salivary structures by 0.9-1.6Gy and provided mean dose reductions of 5.6Gy and 3.9Gy to the composite swallowing structures and oral cavity, respectively. Re-running AIO five times, resulted in the aforementioned parameters differing by less than 3%. CONCLUSIONS Using the same planning strategy as manually optimized head and neck plans, AIO can automate the interactive Eclipse treatment planning process and deliver dosimetric improvements over existing clinical plans.
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Affiliation(s)
- Jim P Tol
- Department of Radiotherapy, VU University Medical Center, De Boelelaan 1117, 1081 HV, Amsterdam, The Netherlands.
| | - Max Dahele
- Department of Radiotherapy, VU University Medical Center, De Boelelaan 1117, 1081 HV, Amsterdam, The Netherlands.
| | - Jarkko Peltola
- Varian Medical Systems, Paciuksenkatu 21, 00270, Helsinki, Finland.
| | - Janne Nord
- Varian Medical Systems, Paciuksenkatu 21, 00270, Helsinki, Finland.
| | - Ben J Slotman
- Department of Radiotherapy, VU University Medical Center, De Boelelaan 1117, 1081 HV, Amsterdam, The Netherlands.
| | - Wilko F A R Verbakel
- Department of Radiotherapy, VU University Medical Center, De Boelelaan 1117, 1081 HV, Amsterdam, The Netherlands.
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191
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Petersson K, Nilsson P, Engström P, Knöös T, Ceberg C. Multi-modality optimisation in radiotherapy treatment planning using composite objective values. Acta Oncol 2015; 54:552-6. [PMID: 25178091 DOI: 10.3109/0284186x.2014.953255] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Kristoffer Petersson
- Department of Medical Radiation Physics, Clinical Sciences, Lund, Lund University , Lund , Sweden
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192
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van de Water S, Kooy HM, Heijmen BJM, Hoogeman MS. Shortening delivery times of intensity modulated proton therapy by reducing proton energy layers during treatment plan optimization. Int J Radiat Oncol Biol Phys 2015; 92:460-8. [PMID: 25823447 DOI: 10.1016/j.ijrobp.2015.01.031] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Revised: 01/16/2015] [Accepted: 01/23/2015] [Indexed: 11/28/2022]
Abstract
PURPOSE To shorten delivery times of intensity modulated proton therapy by reducing the number of energy layers in the treatment plan. METHODS AND MATERIALS We have developed an energy layer reduction method, which was implemented into our in-house-developed multicriteria treatment planning system "Erasmus-iCycle." The method consisted of 2 components: (1) minimizing the logarithm of the total spot weight per energy layer; and (2) iteratively excluding low-weighted energy layers. The method was benchmarked by comparing a robust "time-efficient plan" (with energy layer reduction) with a robust "standard clinical plan" (without energy layer reduction) for 5 oropharyngeal cases and 5 prostate cases. Both plans of each patient had equal robust plan quality, because the worst-case dose parameters of the standard clinical plan were used as dose constraints for the time-efficient plan. Worst-case robust optimization was performed, accounting for setup errors of 3 mm and range errors of 3% + 1 mm. We evaluated the number of energy layers and the expected delivery time per fraction, assuming 30 seconds per beam direction, 10 ms per spot, and 400 Giga-protons per minute. The energy switching time was varied from 0.1 to 5 seconds. RESULTS The number of energy layers was on average reduced by 45% (range, 30%-56%) for the oropharyngeal cases and by 28% (range, 25%-32%) for the prostate cases. When assuming 1, 2, or 5 seconds energy switching time, the average delivery time was shortened from 3.9 to 3.0 minutes (25%), 6.0 to 4.2 minutes (32%), or 12.3 to 7.7 minutes (38%) for the oropharyngeal cases, and from 3.4 to 2.9 minutes (16%), 5.2 to 4.2 minutes (20%), or 10.6 to 8.0 minutes (24%) for the prostate cases. CONCLUSIONS Delivery times of intensity modulated proton therapy can be reduced substantially without compromising robust plan quality. Shorter delivery times are likely to reduce treatment uncertainties and costs.
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Affiliation(s)
- Steven van de Water
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands.
| | - Hanne M Kooy
- F. H. Burr Proton Therapy Center, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - Ben J M Heijmen
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Mischa S Hoogeman
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
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193
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Rossi L, Breedveld S, Aluwini S, Heijmen B. Noncoplanar Beam Angle Class Solutions to Replace Time-Consuming Patient-Specific Beam Angle Optimization in Robotic Prostate Stereotactic Body Radiation Therapy. Int J Radiat Oncol Biol Phys 2015; 92:762-70. [PMID: 26104931 DOI: 10.1016/j.ijrobp.2015.03.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 03/06/2015] [Accepted: 03/17/2015] [Indexed: 11/24/2022]
Abstract
PURPOSE To investigate development of a recipe for the creation of a beam angle class solution (CS) for noncoplanar prostate stereotactic body radiation therapy to replace time-consuming individualized beam angle selection (iBAS) without significant loss in plan quality, using the in-house "Erasmus-iCycle" optimizer for fully automated beam profile optimization and iBAS. METHODS AND MATERIALS For 30 patients, Erasmus-iCycle was first used to generate 15-, 20-, and 25-beam iBAS plans for a CyberKnife equipped with a multileaf collimator. With these plans, 6 recipes for creation of beam angle CSs were investigated. Plans of 10 patients were used to create CSs based on the recipes, and the other 20 to independently test them. For these tests, Erasmus-iCycle was also used to generate intensity modulated radiation therapy plans for the fixed CS beam setups. RESULTS Of the tested recipes for CS creation, only 1 resulted in 15-, 20-, and 25-beam noncoplanar CSs without plan deterioration compared with iBAS. For the patient group, mean differences in rectum D1cc, V60GyEq, V40GyEq, and Dmean between 25-beam CS plans and 25-beam plans generated with iBAS were 0.2 ± 0.4 Gy, 0.1% ± 0.2%, 0.2% ± 0.3%, and 0.1 ± 0.2 Gy, respectively. Differences between 15- and 20-beam CS and iBAS plans were also negligible. Plan quality for CS plans relative to iBAS plans was also preserved when narrower planning target volume margins were arranged and when planning target volume dose inhomogeneity was decreased. Using a CS instead of iBAS reduced the computation time by a factor of 14 to 25, mainly depending on beam number, without loss in plan quality. CONCLUSIONS A recipe for creation of robust beam angle CSs for robotic prostate stereotactic body radiation therapy has been developed. Compared with iBAS, computation times decreased by a factor 14 to 25. The use of a CS may avoid long planning times without losses in plan quality.
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Affiliation(s)
- Linda Rossi
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands.
| | - Sebastiaan Breedveld
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Shafak Aluwini
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Ben Heijmen
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
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Unkelbach J, Bortfeld T, Craft D, Alber M, Bangert M, Bokrantz R, Chen D, Li R, Xing L, Men C, Nill S, Papp D, Romeijn E, Salari E. Optimization approaches to volumetric modulated arc therapy planning. Med Phys 2015; 42:1367-77. [PMID: 25735291 PMCID: PMC5148175 DOI: 10.1118/1.4908224] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Revised: 01/28/2015] [Accepted: 02/04/2015] [Indexed: 12/15/2022] Open
Abstract
Volumetric modulated arc therapy (VMAT) has found widespread clinical application in recent years. A large number of treatment planning studies have evaluated the potential for VMAT for different disease sites based on the currently available commercial implementations of VMAT planning. In contrast, literature on the underlying mathematical optimization methods used in treatment planning is scarce. VMAT planning represents a challenging large scale optimization problem. In contrast to fluence map optimization in intensity-modulated radiotherapy planning for static beams, VMAT planning represents a nonconvex optimization problem. In this paper, the authors review the state-of-the-art in VMAT planning from an algorithmic perspective. Different approaches to VMAT optimization, including arc sequencing methods, extensions of direct aperture optimization, and direct optimization of leaf trajectories are reviewed. Their advantages and limitations are outlined and recommendations for improvements are discussed.
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Affiliation(s)
- Jan Unkelbach
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114
| | - Thomas Bortfeld
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114
| | - David Craft
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114
| | - Markus Alber
- Department of Medical Physics and Department of Radiation Oncology, Aarhus University Hospital, Aarhus C DK-8000, Denmark
| | - Mark Bangert
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center, Heidelberg D-69120, Germany
| | | | - Danny Chen
- Department of Computer Science and Engineering, University of Notre Dame, Notre Dame, Indiana 46556
| | - Ruijiang Li
- Department of Radiation Oncology, Stanford University, Stanford, California 94305
| | - Lei Xing
- Department of Radiation Oncology, Stanford University, Stanford, California 94305
| | - Chunhua Men
- Department of Research, Elekta, Maryland Heights, Missouri 63043
| | - Simeon Nill
- Joint Department of Physics at The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London SM2 5NG, United Kingdom
| | - Dávid Papp
- Department of Mathematics, North Carolina State University, Raleigh, North Carolina 27695
| | - Edwin Romeijn
- H. Milton Stewart School of Industrial and Systems Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Ehsan Salari
- Department of Industrial and Manufacturing Engineering, Wichita State University, Wichita, Kansas 67260
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195
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Sharfo AWM, Voet PWJ, Breedveld S, Mens JWM, Hoogeman MS, Heijmen BJM. Comparison of VMAT and IMRT strategies for cervical cancer patients using automated planning. Radiother Oncol 2015; 114:395-401. [PMID: 25725503 DOI: 10.1016/j.radonc.2015.02.006] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 02/04/2015] [Accepted: 02/09/2015] [Indexed: 11/26/2022]
Abstract
BACKGROUND AND PURPOSE In a published study on cervical cancer, 5-beam IMRT was inferior to single arc VMAT. Here we compare 9, 12, and 20 beam IMRT with single and dual arc VMAT. MATERIAL AND METHODS For each of 10 patients, automated plan generation with the in-house Erasmus-iCycle optimizer was used to assist an expert planner in generating the five plans with the clinical TPS. RESULTS For each patient, all plans were clinically acceptable with a high and similar PTV coverage. OAR sparing increased when going from 9 to 12 to 20 IMRT beams, and from single to dual arc VMAT. For all patients, 12 and 20 beam IMRT were superior to single and dual arc VMAT, with substantial variations in gain among the study patients. As expected, delivery of VMAT plans was significantly faster than delivery of IMRT plans. CONCLUSIONS Often reported increased plan quality for VMAT compared to IMRT has not been observed for cervical cancer. Twenty and 12 beam IMRT plans had a higher quality than single and dual arc VMAT. For individual patients, the optimal delivery technique depends on a complex trade-off between plan quality and treatment time that may change with introduction of faster delivery systems.
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Affiliation(s)
- Abdul Wahab M Sharfo
- Department of Radiation Oncology, Erasmus MC-Cancer Institute, Rotterdam, The Netherlands.
| | - Peter W J Voet
- Department of Radiation Oncology, Erasmus MC-Cancer Institute, Rotterdam, The Netherlands
| | - Sebastiaan Breedveld
- Department of Radiation Oncology, Erasmus MC-Cancer Institute, Rotterdam, The Netherlands
| | - Jan Willem M Mens
- Department of Radiation Oncology, Erasmus MC-Cancer Institute, Rotterdam, The Netherlands
| | - Mischa S Hoogeman
- Department of Radiation Oncology, Erasmus MC-Cancer Institute, Rotterdam, The Netherlands
| | - Ben J M Heijmen
- Department of Radiation Oncology, Erasmus MC-Cancer Institute, Rotterdam, The Netherlands
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196
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Yuan L, Wu QJ, Yin F, Li Y, Sheng Y, Kelsey CR, Ge Y. Standardized beam bouquets for lung IMRT planning. Phys Med Biol 2015; 60:1831-43. [PMID: 25658486 DOI: 10.1088/0031-9155/60/5/1831] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The selection of the incident angles of the treatment beams is a critical component of intensity modulated radiation therapy (IMRT) planning for lung cancer due to significant variations in tumor location, tumor size and patient anatomy. We investigate the feasibility of establishing a small set of standardized beam bouquets for planning. The set of beam bouquets were determined by learning the beam configuration features from 60 clinical lung IMRT plans designed by experienced planners. A k-medoids cluster analysis method was used to classify the beam configurations in the dataset. The appropriate number of clusters was determined by maximizing the value of average silhouette width of the classification. Once the number of clusters had been determined, the beam arrangements in each medoid of the clusters were designated as the standardized beam bouquet for the cluster. This standardized bouquet set was used to re-plan 20 cases randomly selected from the clinical database. The dosimetric quality of the plans using the beam bouquets was evaluated against the corresponding clinical plans by a paired t-test. The classification with six clusters has the largest average silhouette width value and hence would best represent the beam bouquet patterns in the dataset. The results shows that plans generated with a small number of standardized bouquets (e.g. 6) have comparable quality to that of clinical plans. These standardized beam configuration bouquets will potentially help improve plan efficiency and facilitate automated planning.
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Affiliation(s)
- Lulin Yuan
- Department of Radiation Oncology, Duke University Medical Center, Durham, NC, USA
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197
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Tol JP, Delaney AR, Dahele M, Slotman BJ, Verbakel WFAR. Evaluation of a knowledge-based planning solution for head and neck cancer. Int J Radiat Oncol Biol Phys 2015; 91:612-20. [PMID: 25680603 DOI: 10.1016/j.ijrobp.2014.11.014] [Citation(s) in RCA: 214] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 10/16/2014] [Accepted: 11/11/2014] [Indexed: 11/18/2022]
Abstract
PURPOSE Automated and knowledge-based planning techniques aim to reduce variations in plan quality. RapidPlan uses a library consisting of different patient plans to make a model that can predict achievable dose-volume histograms (DVHs) for new patients and uses those models for setting optimization objectives. We benchmarked RapidPlan versus clinical plans for 2 patient groups, using 3 different libraries. METHODS AND MATERIALS Volumetric modulated arc therapy plans of 60 recent head and neck cancer patients that included sparing of the salivary glands, swallowing muscles, and oral cavity were evenly divided between 2 models, Model(30A) and Model(30B), and were combined in a third model, Model60. Knowledge-based plans were created for 2 evaluation groups: evaluation group 1 (EG1), consisting of 15 recent patients, and evaluation group 2 (EG2), consisting of 15 older patients in whom only the salivary glands were spared. RapidPlan results were compared with clinical plans (CP) for boost and/or elective planning target volume homogeneity index, using HI(B)/HI(E) = 100 × (D2% - D98%)/D50%, and mean dose to composite salivary glands, swallowing muscles, and oral cavity (D(sal), D(swal), and D(oc), respectively). RESULTS For EG1, RapidPlan improved HI(B) and HI(E) values compared with CP by 1.0% to 1.3% and 1.0% to 0.6%, respectively. Comparable D(sal) and D(swal) values were seen in Model(30A), Model(30B), and Model60, decreasing by an average of 0.1, 1.0, and 0.8 Gy and 4.8, 3.7, and 4.4 Gy, respectively. However, differences were noted between individual organs at risk (OARs), with Model(30B) increasing D(oc) by 0.1, 3.2, and 2.8 Gy compared with CP, Model(30A), and Model60. Plan quality was less consistent when the patient was flagged as an outlier. For EG2, RapidPlan decreased D(sal) by 4.1 to 4.9 Gy on average, whereas HI(B) and HI(E) decreased by 1.1% to 1.5% and 2.3% to 1.9%, respectively. CONCLUSIONS RapidPlan knowledge-based treatment plans were comparable to CP if the patient's OAR-planning target volume geometry was within the range of those included in the models. EG2 results showed that a model including swallowing-muscle and oral-cavity sparing can be applied to patients with only salivary gland sparing. This may allow model library sharing between institutes. Optimal detection of inadequate plans and population of model libraries requires further investigation.
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Affiliation(s)
- Jim P Tol
- Department of Radiotherapy, VU University Medical Center, Amsterdam, The Netherlands.
| | - Alexander R Delaney
- Department of Radiotherapy, VU University Medical Center, Amsterdam, The Netherlands
| | - Max Dahele
- Department of Radiotherapy, VU University Medical Center, Amsterdam, The Netherlands
| | - Ben J Slotman
- Department of Radiotherapy, VU University Medical Center, Amsterdam, The Netherlands
| | - Wilko F A R Verbakel
- Department of Radiotherapy, VU University Medical Center, Amsterdam, The Netherlands
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198
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Zarepisheh M, Long T, Li N, Tian Z, Romeijn HE, Jia X, Jiang SB. A DVH-guided IMRT optimization algorithm for automatic treatment planning and adaptive radiotherapy replanning. Med Phys 2015; 41:061711. [PMID: 24877806 DOI: 10.1118/1.4875700] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE To develop a novel algorithm that incorporates prior treatment knowledge into intensity modulated radiation therapy optimization to facilitate automatic treatment planning and adaptive radiotherapy (ART) replanning. METHODS The algorithm automatically creates a treatment plan guided by the DVH curves of a reference plan that contains information on the clinician-approved dose-volume trade-offs among different targets/organs and among different portions of a DVH curve for an organ. In ART, the reference plan is the initial plan for the same patient, while for automatic treatment planning the reference plan is selected from a library of clinically approved and delivered plans of previously treated patients with similar medical conditions and geometry. The proposed algorithm employs a voxel-based optimization model and navigates the large voxel-based Pareto surface. The voxel weights are iteratively adjusted to approach a plan that is similar to the reference plan in terms of the DVHs. If the reference plan is feasible but not Pareto optimal, the algorithm generates a Pareto optimal plan with the DVHs better than the reference ones. If the reference plan is too restricting for the new geometry, the algorithm generates a Pareto plan with DVHs close to the reference ones. In both cases, the new plans have similar DVH trade-offs as the reference plans. RESULTS The algorithm was tested using three patient cases and found to be able to automatically adjust the voxel-weighting factors in order to generate a Pareto plan with similar DVH trade-offs as the reference plan. The algorithm has also been implemented on a GPU for high efficiency. CONCLUSIONS A novel prior-knowledge-based optimization algorithm has been developed that automatically adjust the voxel weights and generate a clinical optimal plan at high efficiency. It is found that the new algorithm can significantly improve the plan quality and planning efficiency in ART replanning and automatic treatment planning.
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Affiliation(s)
- Masoud Zarepisheh
- Department of Radiation Medicine and Applied Sciences and Center for Advanced Radiotherapy Technologies, University of California San Diego, La Jolla, California 92037-0843
| | - Troy Long
- Department of Industrial and Operations Engineering, University of Michigan, Ann Arbor, Michigan 48109-2117
| | - Nan Li
- Department of Radiation Medicine and Applied Sciences and Center for Advanced Radiotherapy Technologies, University of California San Diego, La Jolla, California 92037-0843
| | - Zhen Tian
- Department of Radiation Medicine and Applied Sciences and Center for Advanced Radiotherapy Technologies, University of California San Diego, La Jolla, California 92037-0843 and Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-8542
| | - H Edwin Romeijn
- Department of Industrial and Operations Engineering, University of Michigan, Ann Arbor, Michigan 48109-2117
| | - Xun Jia
- Department of Radiation Medicine and Applied Sciences and Center for Advanced Radiotherapy Technologies, University of California San Diego, La Jolla, California 92037-0843 and Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-8542
| | - Steve B Jiang
- Department of Radiation Medicine and Applied Sciences and Center for Advanced Radiotherapy Technologies, University of California San Diego, La Jolla, California 92037-0843 and Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-8542
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Wang B, Wang J, Li J, Fan J, Kang J, Ma CMC. A New Beam Selection Method for MLC-Based Robotic Radiotherapy. ACTA ACUST UNITED AC 2015. [DOI: 10.4236/ijmpcero.2015.42018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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200
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Popple RA, Brezovich IA, Fiveash JB. Beam geometry selection using sequential beam addition. Med Phys 2014; 41:051713. [PMID: 24784379 DOI: 10.1118/1.4870977] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE The selection of optimal beam geometry has been of interest since the inception of conformal radiotherapy. The authors report on sequential beam addition, a simple beam geometry selection method, for intensity modulated radiation therapy. METHODS The sequential beam addition algorithm (SBA) requires definition of an objective function (score) and a set of candidate beam geometries (pool). In the first iteration, the optimal score is determined for each beam in the pool and the beam with the best score selected. In the next iteration, the optimal score is calculated for each beam remaining in the pool combined with the beam selected in the first iteration, and the best scoring beam is selected. The process is repeated until the desired number of beams is reached. The authors selected three treatment sites, breast, lung, and brain, and determined beam arrangements for up to 11 beams from a pool comprised of 25 equiangular transverse beams. For the brain, arrangements were additionally selected from a pool of 22 noncoplanar beams. Scores were determined for geometries comprised equiangular transverse beams (EQA), as well as two tangential beams for the breast case. RESULTS In all cases, SBA resulted in scores superior to EQA. The breast case had the strongest dependence on beam geometry, for which only the 7-beam EQA geometry had a score better than the two tangential beams, whereas all SBA geometries with more than two beams were superior. In the lung case, EQA and SBA scores monotonically improved with increasing number of beams; however, SBA required fewer beams to achieve scores equivalent to EQA. For the brain case, SBA with a coplanar pool was equivalent to EQA, while the noncoplanar pool resulted in slightly better scores; however, the dose-volume histograms demonstrated that the differences were not clinically significant. CONCLUSIONS For situations in which beam geometry has a significant effect on the objective function, SBA can identify arrangements equivalent to equiangular geometries but using fewer beams. Furthermore, SBA provides the value of the objective function as the number of beams is increased, allowing the planner to select the minimal beam number that achieves the clinical goals. The method is simple to implement and could readily be incorporated into an existing optimization system.
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Affiliation(s)
- Richard A Popple
- Department of Radiation Oncology, The University of Alabama at Birmingham, 1720 2nd Avenue South, Birmingham, Alabama 35294
| | - Ivan A Brezovich
- Department of Radiation Oncology, The University of Alabama at Birmingham, 1720 2nd Avenue South, Birmingham, Alabama 35294
| | - John B Fiveash
- Department of Radiation Oncology, The University of Alabama at Birmingham, 1720 2nd Avenue South, Birmingham, Alabama 35294
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