Evidence map›Paper›PMID 41373118›Full record

ArticleJournal of applied clinical medical physics2025

Combined application of block and modulation factors to reduce the volume of the low dose area in helical tomotherapy plans for lung cancer.

Sijin Zhu, Tianwen Zhang, Yutao Zhao, Jinli Peng, Jingyan Gao, Yunyan Yang, Yan Xu, Jiawen Yan, Ya Li

Abstract read
In one paragraph

Article in Journal of applied clinical 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.

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0cells of the map it votes in
1citing papers in PubMed
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1 · What the graph read from it

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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.

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4 · The record

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5 · Who and what money

Authors and funding

9 authors.

Sijin ZhuDepartment of Radiation Oncology, Yunnan Cancer Hospital, The Third Affiliated Hospital of Kunming Medical University, Peking University Cancer Hospital Yunnan, Kunming, Yunnan, China.
Tianwen ZhangDepartment of Radiation Oncology, Yunnan Cancer Hospital, The Third Affiliated Hospital of Kunming Medical University, Peking University Cancer Hospital Yunnan, Kunming, Yunnan, China.
Yutao ZhaoDepartment of Radiation Oncology, Yunnan Cancer Hospital, The Third Affiliated Hospital of Kunming Medical University, Peking University Cancer Hospital Yunnan, Kunming, Yunnan, China.
Jinli PengDepartment of Radiation Oncology, Yunnan Cancer Hospital, The Third Affiliated Hospital of Kunming Medical University, Peking University Cancer Hospital Yunnan, Kunming, Yunnan, China.
Jingyan GaoDepartment of Radiation Oncology, Yunnan Cancer Hospital, The Third Affiliated Hospital of Kunming Medical University, Peking University Cancer Hospital Yunnan, Kunming, Yunnan, China.
Yunyan YangDepartment of Radiation Oncology, Yunnan Cancer Hospital, The Third Affiliated Hospital of Kunming Medical University, Peking University Cancer Hospital Yunnan, Kunming, Yunnan, China.
Yan XuDepartment of Radiation Oncology, Yunnan Cancer Hospital, The Third Affiliated Hospital of Kunming Medical University, Peking University Cancer Hospital Yunnan, Kunming, Yunnan, China.
Jiawen YanDepartment of Radiation Oncology, Yunnan Cancer Hospital, The Third Affiliated Hospital of Kunming Medical University, Peking University Cancer Hospital Yunnan, Kunming, Yunnan, China.
Ya LiDepartment of Radiation Oncology, Yunnan Cancer Hospital, The Third Affiliated Hospital of Kunming Medical University, Peking University Cancer Hospital Yunnan, Kunming, Yunnan, China.ORCID https://orcid.org/0009-0004-2654-8303

Funding

Kunming Medical University Innovation Fund for Graduate Education 2024S352Yunnan Fundamental Research Projects 202301AY070001-240Yunnan Fundamental Research Projects 202401AT070014Yunnan Provincial Department of Science and Technology-Kunming Medical University Joint Special Project for Applied Basic Research 202201AY070001-161
6 · The paper itself

Abstract

backgroundThe helical tomotherapy (HT) system can expose more normal lung tissue to low radiation doses, resulting in extensive low-dose distribution in both lungs which may induce radiation pneumonitis (RP). PURPOSE: This study aims to optimize dosimetric parameters and identify a clinically feasible treatment plan by analyzing the impact of different block settings and modulation factor (MF) combinations on HT plans for lung cancer to reduce the low-dose exposure volumes in normal lung tissue.

methodsWe retrospectively reviewed 14 lung cancer patients who received radiotherapy. These cases were optimized using different modulation factors (MFs: 3, 4, 5) and block techniques (Unblocked, Directional, Complete). The impact of MF and block combinations on reducing low-dose bath (e.g., V5, V10) in lung tissue was evaluated by analyzing dose distribution maps, dose-volume histograms (DVH), homogeneity index (HI), conformity index (CI), and treatment time for each optimized HT plan combination.

resultsBlock settings and higher MF exerted minimal influence on the average dose to the target volume. With stricter block constraints and higher MF, HI increased (range: 17.39%-27.54%) and CI decreased (range: 2.76%-17.43%); although both indices showed slight deterioration, they remained within acceptable clinical limits. Treatment time increased substantially (range: 15.77%-131.58%). The block technique significantly reduced V5 in the bilateral lungs and the contralateral (healthy) lung, with less impact on the ipsilateral (affected) lung. The combination of block and high MF effectively reduced V5.

conclusionsTo balance target volume coverage (high dose), dose distribution uniformity, and treatment duration while reducing low-dose irradiation to normal lung tissue, we recommend implementing Directional block with an MF range of 3-4 to optimize the HT plan for patients with unilateral lung cancer.

Indexed as

Lung NeoplasmsOrgans at RiskRadiotherapy, Intensity-ModulatedRadiotherapy Planning, Computer-AssistedAgedFemaleHumansMaleMiddle AgedRadiotherapy DosageRetrospective Studiesblockhelical tomotherapylung cancermodulation factorspneumonitis

Identifiers

PMID41373118
PMCPMC12695696

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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.