Evidence map›Paper›PMID 40165618›Full record

ArticleMedical physics2025

Impact of range uncertainties for intensity-modulated mixed electron-photon radiation therapy.

Veng Jean Heng, Marc-André Renaud, Monica Serban, Jan Seuntjens

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Article in Medical physics, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
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1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

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2 · The registry

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3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Article
4 · The record

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5 · Who and what money

Authors and funding

4 authors.

Veng Jean HengDepartment of Physics, McGill University, Montreal, Canada.
Marc-André RenaudGray Oncology Solutions, Montreal, Canada.
Monica SerbanMedical Physics Unit, McGill University, Montreal, Canada.
Jan SeuntjensMedical Physics Unit, McGill University, Montreal, Canada.

Funding

CIHR FDN-143257Fonds de recherche du Québec - Nature et technologies 290039
6 · The paper itself

Abstract

backgroundIn the context of mixed electron-photon radiation therapy (MBRT), while the necessity of robust optimization to setup uncertainties is well-established, range uncertainties have yet to be investigated. PURPOSE: This study provides the first assessment of the impact of range uncertainties on MBRT plans.

methodsThe percent depth dose of 2 electron beams (6 MeV and 20 MeV) and 1 photon beam (6 MV) are calculated by Monte Carlo using EGSnrc in slab phantoms. Range uncertainties are simulated by generating two copies of the phantom with each voxel's mass density upscaled or downscaled by 3.5%. Two clinical plans for a leg sarcoma case and a post-mastectomy breast case were replanned with MBRT with 2 optimization methods: once without robust optimization and once with robust to both setup and range uncertainties.

resultsDose discrepancies between the percent depth doses of density-scaled phantoms and the nominal phantom were found to be much larger for electron beams than photons with maximum differences of 6.9% (6 MeV) and 5.5% (20 MeV) versus 1.6% (6 MV) of the maximum dose. In both clinical cases, the region of largest dose discrepancy between the range and nominal scenarios was found to be along the electron's beam path, starting immediately downstream from the target and within a few cm. Even without robust optimization, dose-volume histograms (DVHs) of all relevant structures were not meaningfully degraded under range scenarios. In the breast plan, the ipsilateral lung's V20Gy increased by 1.9% under the worst range scenario. No substantial change in the DVHs of range scenarios were observed between the robustly and non-robustly optimized plan.

conclusionIn the two investigated cases, robustness to range uncertainties was not improved in robustly optimized versus non-robustly optimized plans. A larger study comprising more patients and treatment sites remains to be performed to adequately assess the necessity of robust optimization of MBRT plans to range uncertainties.

Indexed as

ElectronsPhotonsRadiotherapy, Intensity-ModulatedBreast NeoplasmsHumansMonte Carlo MethodPhantoms, ImagingRadiotherapy DosageRadiotherapy Planning, Computer-AssistedUncertaintymixed beam radiation therapyrange uncertaintyrobust optimization

Identifiers

PMID40165618
PMCPMC12149697

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.