{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T16:20:42Z","timestamp":1791994842607,"version":"4.4.0"},"reference-count":31,"publisher":"IOP Publishing","issue":"2","license":[{"start":{"date-parts":[[2020,1,16]],"date-time":"2020-01-16T00:00:00Z","timestamp":1579132800000},"content-version":"vor","delay-in-days":15,"URL":"https:\/\/publishingsupport.iopscience.iop.org\/iop-standard\/v1"},{"start":{"date-parts":[[2020,1,16]],"date-time":"2020-01-16T00:00:00Z","timestamp":1579132800000},"content-version":"tdm","delay-in-days":15,"URL":"https:\/\/iopscience.iop.org\/info\/page\/text-and-data-mining"}],"content-domain":{"domain":["iopscience.iop.org"],"crossmark-restriction":false},"short-container-title":["Phys. Med. Biol."],"published-print":{"date-parts":[[2020,1,1]]},"abstract":"Abstract<\/jats:title>\n \n The relative biological effectiveness (RBE) of protons is highly variable and difficult to quantify. However, RBE is related to the local ionization density, which can be related to the physical measurable dose weighted linear energy transfer (LET\n D<\/jats:sub>\n ). The aim of this study was to validate the LET\n D<\/jats:sub>\n calculations for proton therapy beams implemented in a commercially available treatment planning system (TPS) using microdosimetry measurements and independent LET\n D<\/jats:sub>\n calculations (Open-MCsquare (MCS)).\n <\/jats:p>\n \n The TPS (RayStation v6R) was used to generate treatment plans on the CIRS-731-HN anthropomorphic phantom for three anatomical sites (brain, nasopharynx, neck) for a spherical target (\u00d8\u2009\u2009=\u2009\u20095\u2009cm) with uniform target dose to calculate the LET\n D<\/jats:sub>\n distribution. Measurements were performed at the University Medical Center Groningen proton therapy center (Proteus Plus, IBA) using a\n \u00b5<\/jats:italic>\n +<\/jats:sup>\n -probe utilizing silicon on insulator microdosimeters capable of detecting lineal energies as low as 0.15\u2009keV\n \u00b5<\/jats:italic>\n m\n \u22121<\/jats:sup>\n in tissue. Dose averaged mean lineal energy\n \n depth-profiles were measured for 70 and 130 MeV spots in water and for the three treatment plans in water and an anthropomorphic phantom. The\n \n measurements were compared to the LET\n D<\/jats:sub>\n calculated in the TPS and MCS independent dose calculation engine. D \u00b7\n \n was compared to D \u00b7 LET\n D<\/jats:sub>\n in terms of a gamma-index with a distance-to-agreement criteria of 2\u2009mm and increasing dose difference criteria to determine the criteria for which a 90% pass rate was accomplished.\n <\/jats:p>\n \n Measurements of D \u00b7\n \n were in good agreement with the D \u00b7 LET\n D<\/jats:sub>\n calculated in the TPS and MCS. The 90% passing rate threshold was reached at different D \u00b7 LET\n D<\/jats:sub>\n difference criteria for single spots (TPS: 1% MCS: 1%), treatment plans in water (TPS: 3% MCS: 6%) and treatment plans in an anthropomorphic phantom (TPS: 6% MCS: 1%).\n <\/jats:p>\n \n We conclude that D \u00b7 LET\n D<\/jats:sub>\n calculations accuracy in the RayStation TPS and open MCSquare are within 6%, and sufficient for clinical D \u00b7 LET\n D<\/jats:sub>\n evaluation and optimization. These findings remove an important obstacle in the road towards clinical implementation of D \u00b7 LET\n D<\/jats:sub>\n evaluation and optimization of proton therapy treatment plans.\n <\/jats:p>\n \n Novelty and significance<\/jats:bold>\n <\/jats:p>\n \n The dose weighed linear energy transfer (LET\n D<\/jats:sub>\n ) distribution can be calculated for proton therapy treatment plans by Monte Carlo dose engines. The relative biological effectiveness (RBE) of protons is known to vary with the LET\n D<\/jats:sub>\n distribution. Therefore, there exists a need for accurate calculation of clinical LET\n D<\/jats:sub>\n distributions. Previous LET\n D<\/jats:sub>\n validations have focused on general purpose Monte Carlo dose engines which are typically not used clinically. We present the first validation of mean lineal energy\n \n measurements of the LET\n D<\/jats:sub>\n against calculations by the Monte Carlo dose engines of the Raystation treatment planning system and open MCSquare.\n <\/jats:p>","DOI":"10.1088\/1361-6560\/ab5e97","type":"journal-article","created":{"date-parts":[[2019,12,4]],"date-time":"2019-12-04T17:31:20Z","timestamp":1575480680000},"page":"025006","update-policy":"https:\/\/doi.org\/10.1088\/crossmark-policy","source":"Crossref","is-referenced-by-count":63,"title":["Validation of linear energy transfer computed in a Monte Carlo dose engine of a commercial treatment planning system"],"prefix":"10.1088","volume":"65","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8321-6824","authenticated-orcid":false,"given":"Dirk","family":"Wagenaar","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Linh T","family":"Tran","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arturs","family":"Meijers","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8486-7001","authenticated-orcid":false,"given":"Gabriel Guterres","family":"Marmitt","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kevin","family":"Souris","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David","family":"Bolst","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Benjamin","family":"James","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giordano","family":"Biasi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marco","family":"Povoli","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Angela","family":"Kok","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Erik","family":"Traneus","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marc-Jan","family":"van Goethem","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Johannes A","family":"Langendijk","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anatoly B","family":"Rosenfeld","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefan","family":"Both","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"266","published-online":{"date-parts":[[2020,1,16]]},"reference":[{"key":"pmbab5e97bib001","doi-asserted-by":"publisher","first-page":"6029","DOI":"10.1002\/mp.12583","type":"journal-article","article-title":"Microdosimetric measurements of a clinical proton beam with micrometer-sized solid-state detector","volume":"44","author":"Anderson","year":"2017","journal-title":"Med. Phys."},{"key":"pmbab5e97bib002","doi-asserted-by":"publisher","first-page":"4204","DOI":"10.1002\/mp.13673","type":"journal-article","article-title":"Segment-averaged LET concept and analytical calculation from microdosimetric quantities in proton radiation therapy","volume":"46","author":"Bertolet","year":"2019","journal-title":"Med. Phys."},{"key":"pmbab5e97bib003","doi-asserted-by":"publisher","first-page":"2055","DOI":"10.1088\/1361-6560\/aa5de5","type":"journal-article","article-title":"Correction factors to convert microdosimetry measurements in silicon to tissue in 12C ion therapy","volume":"62","author":"Bolst","year":"2017","journal-title":"Phys. Med. Biol."},{"key":"pmbab5e97bib004","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1120\/jacmp.v8i2.2374","type":"journal-article","article-title":"A study to establish reasonable action limits for patient-specific quality assurance in intensity-modulated radiation therapy","volume":"8","author":"Both","year":"2007","journal-title":"J. Appl. Clin. Med. Phys."},{"key":"pmbab5e97bib005","doi-asserted-by":"publisher","DOI":"10.1088\/1361-6560\/aa9a2e","type":"journal-article","article-title":"Linear energy transfer incorporated intensity modulated proton therapy optimization","volume":"63","author":"Cao","year":"2017","journal-title":"Phys. Med. Biol."},{"key":"pmbab5e97bib006","doi-asserted-by":"publisher","first-page":"27","DOI":"10.1080\/09553000601087176","type":"journal-article","article-title":"The incorporation of the concept of minimum RBE (RbEmin) into the linear-quadratic model and the potential for improved radiobiological analysis of high-LET treatments","volume":"83","author":"Carabe-Fernandez","year":"2007","journal-title":"Int. J. Radiat. Biol."},{"key":"pmbab5e97bib007","doi-asserted-by":"publisher","first-page":"365","DOI":"10.1093\/rpd\/ncx226","type":"journal-article","article-title":"Microdosimetric applications in proton and heavy ion therapy using silicon microdosimeters","volume":"180","author":"Chartier","year":"2017","journal-title":"Radiat. Prot. Dosimetry"},{"key":"pmbab5e97bib008","doi-asserted-by":"publisher","first-page":"2645","DOI":"10.1088\/0031-9155\/60\/7\/2645","type":"journal-article","article-title":"A critical study of different Monte Carlo scoring methods of dose average linear-energy-transfer maps calculated in voxelized geometries irradiated with clinical proton beams","volume":"60","author":"Cort\u00e9s-Giraldo","year":"2015","journal-title":"Phys. Med. Biol."},{"key":"pmbab5e97bib009","doi-asserted-by":"publisher","first-page":"867","DOI":"10.1016\/S0360-3016(03)00197-4","type":"journal-article","article-title":"Patient-specific point dose measurement for IMRT monitor unit verification","volume":"56","author":"Dong","year":"2003","journal-title":"Int. J. Radiat. Oncol. Biol. Phys."},{"key":"pmbab5e97bib010","doi-asserted-by":"publisher","first-page":"5359","DOI":"10.1118\/1.3238104","type":"journal-article","article-title":"IMRT commissioning: multiple institution planning and dosimetry comparisons, a report from AAPM Task Group 119","volume":"36","author":"Ezzell","year":"2009","journal-title":"Med. Phys."},{"key":"pmbab5e97bib011","doi-asserted-by":"publisher","first-page":"68","DOI":"10.1186\/s13014-016-0642-6","type":"journal-article","article-title":"Variable RBE in proton therapy: comparison of different model predictions and their influence on clinical-like scenarios","volume":"11","author":"Giovannini","year":"2016","journal-title":"Radiat. Oncol."},{"key":"pmbab5e97bib012","doi-asserted-by":"publisher","first-page":"5631","DOI":"10.1002\/mp.13231","type":"journal-article","article-title":"Validation and application of a fast Monte Carlo algorithm for assessing the clinical impact of approximations in analytical dose calculations for pencil beam scanning proton therapy","volume":"45","author":"Huang","year":"2018","journal-title":"Med. Phys."},{"key":"pmbab5e97bib013","author":"ICRU","year":"1978","type":"report"},{"key":"pmbab5e97bib014","doi-asserted-by":"publisher","first-page":"156","DOI":"10.1002\/acm2.12235","type":"journal-article","article-title":"A comparison of two pencil beam scanning treatment planning systems for proton therapy","volume":"19","author":"Langner","year":"2018","journal-title":"J. Appl. Clin. Med. Phys."},{"key":"pmbab5e97bib015","doi-asserted-by":"publisher","first-page":"656","DOI":"10.1118\/1.598248","type":"journal-article","article-title":"A technique for the quantitative evaluation of dose distributions","volume":"25","author":"Low","year":"1998","journal-title":"Med. Phys."},{"key":"pmbab5e97bib016","doi-asserted-by":"publisher","DOI":"10.25030\/ncs-024)","type":"report","article-title":"Code of practice for the quality assurance and control for volumetric modulated arc therapy","author":"Mans","year":"2015"},{"key":"pmbab5e97bib017","doi-asserted-by":"publisher","DOI":"10.1088\/1361-6560\/aae8a5","type":"journal-article","article-title":"LET-weighted doses effectively reduce biological variability in proton radiotherapy planning","volume":"63","author":"McMahon","year":"2018","journal-title":"Phys. Med. Biol."},{"key":"pmbab5e97bib018","doi-asserted-by":"publisher","first-page":"8399","DOI":"10.1088\/0031-9155\/60\/21\/8399","type":"journal-article","article-title":"A phenomenological relative biological effectiveness (RBE) model for proton therapy based on all published in vitro cell survival data","volume":"60","author":"McNamara","year":"2015","journal-title":"Phys. Med. Biol."},{"key":"pmbab5e97bib019","doi-asserted-by":"publisher","first-page":"R419","DOI":"10.1088\/0031-9155\/59\/22\/R419","type":"journal-article","article-title":"Relative biological effectiveness (RBE) values for proton beam therapy. Variations as a function of biological endpoint, dose, and linear energy transfer","volume":"59","author":"Paganetti","year":"2014","journal-title":"Phys. Med. Biol."},{"key":"pmbab5e97bib020","doi-asserted-by":"publisher","first-page":"e53","DOI":"10.1002\/mp.13390","type":"journal-article","article-title":"Report of the AAPM TG-256 on the relative biological effectiveness of proton beams in radiation therapy","volume":"46","author":"Paganetti","year":"2019","journal-title":"Med. Phys."},{"key":"pmbab5e97bib021","doi-asserted-by":"publisher","first-page":"4825","DOI":"10.1088\/0031-9155\/53\/17\/023","type":"journal-article","article-title":"Clinical implementation of full Monte Carlo dose calculation in proton beam therapy","volume":"53","author":"Paganetti","year":"2008","journal-title":"Phys. Med. Biol."},{"key":"pmbab5e97bib022","doi-asserted-by":"publisher","first-page":"407","DOI":"10.1016\/S0360-3016(02)02754-2","type":"journal-article","article-title":"Relative biological effectiveness (RBE) values for proton beam therapy","volume":"53","author":"Paganetti","year":"2002","journal-title":"Int. J. Radiat. Oncol. Biol. Phys."},{"key":"pmbab5e97bib023","doi-asserted-by":"publisher","DOI":"10.1088\/1361-6560\/aad9db","type":"journal-article","article-title":"Exploration and application of phenomenological RBE models for proton therapy","volume":"63","author":"R\u00f8rvik","year":"2018","journal-title":"Phys. Med. Biol."},{"key":"pmbab5e97bib024","doi-asserted-by":"publisher","first-page":"156","DOI":"10.1016\/j.nima.2015.08.059","type":"journal-article","article-title":"Novel detectors for silicon based microdosimetry, their concepts and applications","volume":"809","author":"Rosenfeld","year":"2016","journal-title":"Nucl. Instrum. Methods Phys. Res. A"},{"key":"pmbab5e97bib025","doi-asserted-by":"publisher","first-page":"10","DOI":"10.1016\/j.ejmp.2017.04.020","type":"journal-article","article-title":"Experimental assessment of proton dose calculation accuracy in inhomogeneous media","volume":"38","author":"Sorriaux","year":"2017","journal-title":"Phys. Med."},{"key":"pmbab5e97bib026","doi-asserted-by":"publisher","first-page":"1700","DOI":"10.1118\/1.4943377","type":"journal-article","article-title":"Fast multipurpose Monte Carlo simulation for proton therapy using multi- and many-core CPU architectures","volume":"43","author":"Souris","year":"2016","journal-title":"Med. Phys."},{"key":"pmbab5e97bib027","doi-asserted-by":"publisher","first-page":"504","DOI":"10.1109\/TNS.2015.2391102","type":"journal-article","article-title":"3D-Mesa \u2018bridge\u2019 silicon microdosimeter: Charge collection study and application to RBE studies in 12C radiation therapy","volume":"62","author":"Tran","year":"2015","journal-title":"IEEE Trans. Nucl. Sci."},{"key":"pmbab5e97bib028","doi-asserted-by":"publisher","first-page":"6085","DOI":"10.1002\/mp.12563","type":"journal-article","article-title":"Characterization of proton pencil beam scanning and passive beam using a high spatial resolution solid-state microdosimeter","volume":"44","author":"Tran","year":"2017","journal-title":"Med. Phys."},{"key":"pmbab5e97bib029","doi-asserted-by":"publisher","first-page":"747","DOI":"10.1016\/j.ijrobp.2018.10.031","type":"journal-article","article-title":"Introducing proton track-end objectives in intensity modulated proton therapy optimization to reduce linear energy transfer and relative biological effectiveness in critical structures","volume":"103","author":"Traneus","year":"2019","journal-title":"Int. J. Radiat. Oncol. Biol. Phys."},{"key":"pmbab5e97bib030","doi-asserted-by":"publisher","first-page":"1097","DOI":"10.1016\/j.ijrobp.2016.08.038","type":"journal-article","article-title":"Reoptimization of intensity modulated proton therapy plans based on linear energy transfer","volume":"96","author":"Unkelbach","year":"2016","journal-title":"Int. J. Radiat. Oncol. Biol. Phys."},{"key":"pmbab5e97bib031","doi-asserted-by":"publisher","first-page":"580","DOI":"10.3109\/0284186X.2012.705892","type":"journal-article","article-title":"A model for the relative biological effectiveness of protons: the tissue specific parameter \u03b1\/\u03b2 of photons is a predictor for the sensitivity to LET changes","volume":"52","author":"Wedenberg","year":"2013","journal-title":"Acta Oncol."}],"container-title":["Physics in Medicine & Biology"],"original-title":[],"link":[{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1361-6560\/ab5e97","content-type":"text\/html","content-version":"am","intended-application":"text-mining"},{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1361-6560\/ab5e97\/pdf","content-type":"application\/pdf","content-version":"am","intended-application":"text-mining"},{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1361-6560\/ab5e97\/pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1361-6560\/ab5e97","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1361-6560\/ab5e97","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1361-6560\/ab5e97\/pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1361-6560\/ab5e97\/pdf","content-type":"application\/pdf","content-version":"am","intended-application":"syndication"},{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1361-6560\/ab5e97\/pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1361-6560\/ab5e97\/pdf","content-type":"application\/pdf","content-version":"am","intended-application":"similarity-checking"},{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1361-6560\/ab5e97\/pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"},{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1361-6560\/ab5e97","content-type":"text\/html","content-version":"vor","intended-application":"similarity-checking"},{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1361-6560\/ab5e97\/pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,12,13]],"date-time":"2025-12-13T14:20:40Z","timestamp":1765635640000},"score":1,"resource":{"primary":{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1361-6560\/ab5e97"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,1,1]]},"references-count":31,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2020,1,16]]},"published-print":{"date-parts":[[2020,1,1]]}},"URL":"https:\/\/doi.org\/10.1088\/1361-6560\/ab5e97","relation":{},"ISSN":["0031-9155","1361-6560"],"issn-type":[{"value":"0031-9155","type":"print"},{"value":"1361-6560","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,1,1]]},"assertion":[{"value":"Validation of linear energy transfer computed in a Monte Carlo dose engine of a commercial treatment planning system","name":"article_title","label":"Article Title"},{"value":"Physics in Medicine & Biology","name":"journal_title","label":"Journal Title"},{"value":"paper","name":"article_type","label":"Article Type"},{"value":"\u00a9 2020 Institute of Physics and Engineering in Medicine. All rights, including for text and data mining, AI training, and similar technologies, are reserved.","name":"copyright_information","label":"Copyright Information"},{"value":"2019-09-30","name":"date_received","label":"Date Received","group":{"name":"publication_dates","label":"Publication dates"}},{"value":"2019-12-04","name":"date_accepted","label":"Date Accepted","group":{"name":"publication_dates","label":"Publication dates"}},{"value":"2020-01-16","name":"date_epub","label":"Online publication date","group":{"name":"publication_dates","label":"Publication dates"}}]}}