Joseph S. Lee MD, PhD , Derek A. Mumaw MD , Peilin Liu MS , Bailey A. Loving MD , Ebin Sebastian MBBS , Xiaoda Cong MS , Mark S. Stefani PhD , Brian F. Loughery PhD , Xiaoqiang Li PhD , Rohan Deraniyagala MD , Muayad F. Almahariq MD, PhD , Xuanfeng Ding PhD , Thomas J. Quinn MD
{"title":"Rotationally Intensified Proton Lattice: A Novel Lattice Technique Using Spot-Scanning Proton Arc Therapy","authors":"Joseph S. Lee MD, PhD , Derek A. Mumaw MD , Peilin Liu MS , Bailey A. Loving MD , Ebin Sebastian MBBS , Xiaoda Cong MS , Mark S. Stefani PhD , Brian F. Loughery PhD , Xiaoqiang Li PhD , Rohan Deraniyagala MD , Muayad F. Almahariq MD, PhD , Xuanfeng Ding PhD , Thomas J. Quinn MD","doi":"10.1016/j.adro.2024.101632","DOIUrl":null,"url":null,"abstract":"<div><h3>Purpose</h3><div>The aim of this study was to explore the feasibility and dosimetric advantage of using spot-scanning proton arc (SPArc) for lattice radiation therapy in comparison with volumetric-modulated arc therapy (VMAT) and intensity modulated proton therapy (IMPT) lattice techniques.</div></div><div><h3>Methods</h3><div>Lattice plans were retrospectively generated for 14 large tumors across the abdomen, pelvis, lung, and head-and-neck sites using VMAT, IMPT, and SPArc techniques. Lattice geometries comprised vertices 1.5 cm in diameter that were arrayed in a body-centered cubic lattice with a 6-cm lattice constant. The prescription dose was 20 Gy (relative biological effectiveness [RBE]) in 5 fractions to the periphery of the tumor, with a simultaneous integrated boost of 66.7 Gy (RBE) as a minimum dose to the vertices. Organ-at-risk constraints per American Association of Physicists in Medicine Task Group 101were prioritized. Dose-volume histograms were extracted and used to identify maximum, minimum, and mean doses; equivalent uniform dose; D95%, D50%, D10%, D5%; V19Gy; peak-to-valley dose ratio (PVDR); and gradient index (GI). The treatment delivery time of IMPT and SPArc were simulated based on the published proton delivery sequence model.</div></div><div><h3>Results</h3><div>Median tumor volume was 577 cc with a median of 4.5 high-dose vertices per plan. Low-dose coverage was maintained in all plans (median V19Gy: SPArc 96%, IMPT 96%, VMAT 92%). SPArc generated significantly greater dose gradients as measured by PVDR (SPArc 4.0, IMPT 3.6, VMAT 3.2; SPArc-IMPT <em>P</em> = .0001, SPArc-VMAT <em>P</em> < .001) and high-dose GI (SPArc 5.9, IMPT 11.7, VMAT 17.1; SPArc-IMPT <em>P</em> = .001, SPArc-VMAT <em>P</em> < .01). Organ-at-risk constraints were met in all plans. Simulated delivery time was significantly improved with SPArc compared with IMPT (510 seconds vs 637 seconds, <em>P</em> < .001).</div></div><div><h3>Conclusions</h3><div>SPArc therapy was able to achieve high-quality lattice plans for various sites with superior gradient metrics (PVDR and GI) when compared with VMAT and IMPT. Clinical implementation is warranted.</div></div>","PeriodicalId":7390,"journal":{"name":"Advances in Radiation Oncology","volume":"9 11","pages":"Article 101632"},"PeriodicalIF":2.2000,"publicationDate":"2024-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Advances in Radiation Oncology","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2452109424001957","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ONCOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Purpose
The aim of this study was to explore the feasibility and dosimetric advantage of using spot-scanning proton arc (SPArc) for lattice radiation therapy in comparison with volumetric-modulated arc therapy (VMAT) and intensity modulated proton therapy (IMPT) lattice techniques.
Methods
Lattice plans were retrospectively generated for 14 large tumors across the abdomen, pelvis, lung, and head-and-neck sites using VMAT, IMPT, and SPArc techniques. Lattice geometries comprised vertices 1.5 cm in diameter that were arrayed in a body-centered cubic lattice with a 6-cm lattice constant. The prescription dose was 20 Gy (relative biological effectiveness [RBE]) in 5 fractions to the periphery of the tumor, with a simultaneous integrated boost of 66.7 Gy (RBE) as a minimum dose to the vertices. Organ-at-risk constraints per American Association of Physicists in Medicine Task Group 101were prioritized. Dose-volume histograms were extracted and used to identify maximum, minimum, and mean doses; equivalent uniform dose; D95%, D50%, D10%, D5%; V19Gy; peak-to-valley dose ratio (PVDR); and gradient index (GI). The treatment delivery time of IMPT and SPArc were simulated based on the published proton delivery sequence model.
Results
Median tumor volume was 577 cc with a median of 4.5 high-dose vertices per plan. Low-dose coverage was maintained in all plans (median V19Gy: SPArc 96%, IMPT 96%, VMAT 92%). SPArc generated significantly greater dose gradients as measured by PVDR (SPArc 4.0, IMPT 3.6, VMAT 3.2; SPArc-IMPT P = .0001, SPArc-VMAT P < .001) and high-dose GI (SPArc 5.9, IMPT 11.7, VMAT 17.1; SPArc-IMPT P = .001, SPArc-VMAT P < .01). Organ-at-risk constraints were met in all plans. Simulated delivery time was significantly improved with SPArc compared with IMPT (510 seconds vs 637 seconds, P < .001).
Conclusions
SPArc therapy was able to achieve high-quality lattice plans for various sites with superior gradient metrics (PVDR and GI) when compared with VMAT and IMPT. Clinical implementation is warranted.
期刊介绍:
The purpose of Advances is to provide information for clinicians who use radiation therapy by publishing: Clinical trial reports and reanalyses. Basic science original reports. Manuscripts examining health services research, comparative and cost effectiveness research, and systematic reviews. Case reports documenting unusual problems and solutions. High quality multi and single institutional series, as well as other novel retrospective hypothesis generating series. Timely critical reviews on important topics in radiation oncology, such as side effects. Articles reporting the natural history of disease and patterns of failure, particularly as they relate to treatment volume delineation. Articles on safety and quality in radiation therapy. Essays on clinical experience. Articles on practice transformation in radiation oncology, in particular: Aspects of health policy that may impact the future practice of radiation oncology. How information technology, such as data analytics and systems innovations, will change radiation oncology practice. Articles on imaging as they relate to radiation therapy treatment.