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arXiv · 2110.05410

Probabilistic Pareto plan generation for semiautomated multicriteria radiation therapy treatment planning

Tianfang Zhang·Rasmus Bokrantz·Jimmy Olsson
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Abstract

Objective: We propose a semiautomatic pipeline for radiation therapy treatment planning, combining ideas from machine learning-automated planning and multicriteria optimization (MCO). Approach: Using knowledge extracted from historically delivered plans, prediction models for spatial dose and dose statistics are trained and furthermore systematically modified to simulate changes in tradeoff priorities, creating a set of differently biased predictions. Based on the predictions, an MCO problem is subsequently constructed using previously developed dose mimicking functions, designed in such a way that its Pareto surface spans the range of clinically acceptable yet realistically achievable plans as exactly as possible. The result is an algorithm outputting a set of Pareto optimal plans, either fluence-based or machine parameter-based, which the user can navigate between in real time to make adjustments before a final deliverable plan is created. Main results: Numerical experiments performed on a dataset of prostate cancer patients show that one may often navigate to a better plan than one produced by a single-plan-output algorithm. Significance: We demonstrate the potential of merging MCO and a data-driven workflow to automate labor-intensive parts of the treatment planning process while maintaining a certain extent of manual control for the user.

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Tianfang Zhang, Rasmus Bokrantz, Jimmy Olsson. 2021-10-11. Probabilistic Pareto plan generation for semiautomated multicriteria radiation therapy treatment planning. https://doi.org/10.1088/1361-6560%2Fac4da5

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