A reinforcement learning agent for head and neck intensity-modulated radiation therapy

Head and neck (HN) cancers pose a difficult problem in the planning of intensity-modulated radiation therapy (IMRT) treatment. The primary tumor can be large and asymmetrical, and multiple organs at risk (OARs) with varying dose-sparing goals lie close to the target volume. Currently, there is no sy...

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Main Authors: Hunter Stephens, Xinyi Li, Yang Sheng, Qiuwen Wu, Yaorong Ge, Q. Jackie Wu
Format: Article
Language:English
Published: Frontiers Media S.A. 2024-02-01
Series:Frontiers in Physics
Subjects:
Online Access:https://www.frontiersin.org/articles/10.3389/fphy.2024.1331849/full
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author Hunter Stephens
Xinyi Li
Yang Sheng
Qiuwen Wu
Yaorong Ge
Q. Jackie Wu
author_facet Hunter Stephens
Xinyi Li
Yang Sheng
Qiuwen Wu
Yaorong Ge
Q. Jackie Wu
author_sort Hunter Stephens
collection DOAJ
description Head and neck (HN) cancers pose a difficult problem in the planning of intensity-modulated radiation therapy (IMRT) treatment. The primary tumor can be large and asymmetrical, and multiple organs at risk (OARs) with varying dose-sparing goals lie close to the target volume. Currently, there is no systematic way of automating the generation of IMRT plans, and the manual options face planning quality and long planning time challenges. In this article, we present a reinforcement learning (RL) model for the purposes of providing automated treatment planning to reduce clinical workflow time as well as providing a better starting point for human planners to modify and build upon. Several models with progressing complexity are presented, including the relevant plan dosimetry analysis and model interpretations of the resulting strategies learned by the auto-planning agent. Models were trained on a set of 40 patients and validated on a set of 20 patients. The presented models are shown to be consistent with the requirements of an RL model to be underpinned by a Markov decision process (MDP). In-depth interpretability of the models is presented by examination of the decision space using action hyperplanes. The auto-planning agent was able to generate plans with superior reduction in the mean dose of the left and right parotid glands by approximately 7 Gy ± 2.5 Gy (p < 0.01) over a starting, static template plan with only pre-defined general prescription information. RL plans were comparable to a human expert’s clinical plans for the primary (44 Gy), boost (26 Gy) , and the summed plans (70 Gy) with p-values of 0.43, 0.72, and 0.67, respectively, for the dosimetric endpoints and uniform target coverage normalization. The RL planning agent was able to produce the plans used in validation in an average of 13.58 min, with a minimum and a maximum planning time of 2.27 and 44.82 min, respectively.
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spelling doaj.art-a99eb6d2ab604d5ca94234c3e1c6343c2024-02-01T04:20:51ZengFrontiers Media S.A.Frontiers in Physics2296-424X2024-02-011210.3389/fphy.2024.13318491331849A reinforcement learning agent for head and neck intensity-modulated radiation therapyHunter Stephens0Xinyi Li1Yang Sheng2Qiuwen Wu3Yaorong Ge4Q. Jackie Wu5Department of Radiation Oncology, Duke University, Durham, NC, United StatesDepartment of Radiation Oncology, Duke University, Durham, NC, United StatesDepartment of Radiation Oncology, Duke University, Durham, NC, United StatesDepartment of Radiation Oncology, Duke University, Durham, NC, United StatesDepartment of Software and Information Systems, University of North Carolina at Charlotte, Charlotte, NC, United StatesDepartment of Radiation Oncology, Duke University, Durham, NC, United StatesHead and neck (HN) cancers pose a difficult problem in the planning of intensity-modulated radiation therapy (IMRT) treatment. The primary tumor can be large and asymmetrical, and multiple organs at risk (OARs) with varying dose-sparing goals lie close to the target volume. Currently, there is no systematic way of automating the generation of IMRT plans, and the manual options face planning quality and long planning time challenges. In this article, we present a reinforcement learning (RL) model for the purposes of providing automated treatment planning to reduce clinical workflow time as well as providing a better starting point for human planners to modify and build upon. Several models with progressing complexity are presented, including the relevant plan dosimetry analysis and model interpretations of the resulting strategies learned by the auto-planning agent. Models were trained on a set of 40 patients and validated on a set of 20 patients. The presented models are shown to be consistent with the requirements of an RL model to be underpinned by a Markov decision process (MDP). In-depth interpretability of the models is presented by examination of the decision space using action hyperplanes. The auto-planning agent was able to generate plans with superior reduction in the mean dose of the left and right parotid glands by approximately 7 Gy ± 2.5 Gy (p < 0.01) over a starting, static template plan with only pre-defined general prescription information. RL plans were comparable to a human expert’s clinical plans for the primary (44 Gy), boost (26 Gy) , and the summed plans (70 Gy) with p-values of 0.43, 0.72, and 0.67, respectively, for the dosimetric endpoints and uniform target coverage normalization. The RL planning agent was able to produce the plans used in validation in an average of 13.58 min, with a minimum and a maximum planning time of 2.27 and 44.82 min, respectively.https://www.frontiersin.org/articles/10.3389/fphy.2024.1331849/fullreinforcement learningradiation therapyautomated treatment planninghead and neck cancerinterpretable machine learning
spellingShingle Hunter Stephens
Xinyi Li
Yang Sheng
Qiuwen Wu
Yaorong Ge
Q. Jackie Wu
A reinforcement learning agent for head and neck intensity-modulated radiation therapy
Frontiers in Physics
reinforcement learning
radiation therapy
automated treatment planning
head and neck cancer
interpretable machine learning
title A reinforcement learning agent for head and neck intensity-modulated radiation therapy
title_full A reinforcement learning agent for head and neck intensity-modulated radiation therapy
title_fullStr A reinforcement learning agent for head and neck intensity-modulated radiation therapy
title_full_unstemmed A reinforcement learning agent for head and neck intensity-modulated radiation therapy
title_short A reinforcement learning agent for head and neck intensity-modulated radiation therapy
title_sort reinforcement learning agent for head and neck intensity modulated radiation therapy
topic reinforcement learning
radiation therapy
automated treatment planning
head and neck cancer
interpretable machine learning
url https://www.frontiersin.org/articles/10.3389/fphy.2024.1331849/full
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