{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,14]],"date-time":"2026-05-14T17:08:42Z","timestamp":1778778522035,"version":"3.51.4"},"reference-count":44,"publisher":"IOP Publishing","issue":"7","license":[{"start":{"date-parts":[[2021,4,1]],"date-time":"2021-04-01T00:00:00Z","timestamp":1617235200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/publishingsupport.iopscience.iop.org\/iop-standard\/v1"},{"start":{"date-parts":[[2021,4,1]],"date-time":"2021-04-01T00:00:00Z","timestamp":1617235200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/iopscience.iop.org\/info\/page\/text-and-data-mining"}],"funder":[{"DOI":"10.13039\/100012524","name":"American Lebanese Syrian Associated Charities","doi-asserted-by":"crossref","id":[{"id":"10.13039\/100012524","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["iopscience.iop.org"],"crossmark-restriction":false},"short-container-title":["Phys. Med. Biol."],"published-print":{"date-parts":[[2021,4,7]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>\n                    The dosimetric advantages of proton therapy have led to its rapid proliferation in recent decades. This has been accompanied by a shift in technology from older units that deliver protons by passive scattering (PS) to newer units that increasingly use pencil-beam scanning (PBS). The biologic effectiveness of proton physical dose purportedly rises with increasing dose-weighted average linear energy transfer (LET\n                    <jats:sub>D<\/jats:sub>\n                    ). The objective of this study was to determine the extent to which proton delivery methods affect LET\n                    <jats:sub>D<\/jats:sub>\n                    . We calculated LET\n                    <jats:sub>D<\/jats:sub>\n                    from simple, dosimetrically matched, and clinical treatment plans with TOPAS Monte-Carlo transport code. Simple treatment plans comprised single fields of PS and PBS protons in a water phantom. We performed simulations of matched and clinical treatment plans by using the treatment and anatomic data obtained from a cohort of children with craniopharyngioma who previously received PS or PBS proton therapy. We compared the distributions of LET\n                    <jats:sub>D<\/jats:sub>\n                    from PS and PBS delivery methods in clinically relevant ROIs. Wilcoxon signed-rank tests comparing single fields in water revealed that the LET\n                    <jats:sub>D<\/jats:sub>\n                    values from PBS were significantly greater than those from PS inside and outside the targeted volume (\n                    <jats:italic>p<\/jats:italic>\n                    \u00a0&lt;\u00a00.01). Statistical tests comparing LET\n                    <jats:sub>D<\/jats:sub>\n                    -volume histograms from matched and clinical treatment plans showed that LET\n                    <jats:sub>D<\/jats:sub>\n                    was generally greater for PBS treatment plans than for PS treatment plans (\n                    <jats:italic>p<\/jats:italic>\n                    \u00a0&lt;\u00a00.05). In conclusion, the proton delivery method affects LET\n                    <jats:sub>D<\/jats:sub>\n                    both inside and outside of the target volume. These findings suggest that PBS is more biologically effective than PS. Given the rapid expansion of PBS proton therapy, future studies are needed to confirm the applicability of treatment evaluation methods developed for PS proton therapy to those for modern PBS treatments to ensure their safety and effectiveness for the growing population of patients receiving proton therapy. This study uses data from two clinical trials: NCT01419067 and NCT02792582.\n                  <\/jats:p>","DOI":"10.1088\/1361-6560\/abe835","type":"journal-article","created":{"date-parts":[[2021,2,19]],"date-time":"2021-02-19T17:42:48Z","timestamp":1613756568000},"page":"074003","update-policy":"https:\/\/doi.org\/10.1088\/crossmark-policy","source":"Crossref","is-referenced-by-count":2,"title":["Proton therapy delivery method affects dose-averaged linear energy transfer in patients"],"prefix":"10.1088","volume":"66","author":[{"given":"Lydia J","family":"Wilson","sequence":"first","affiliation":[{"name":"St. Jude Children\u2019s Research Hospital, Department of Radiation Oncology, Memphis, TN,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fakhriddin","family":"Pirlepesov","sequence":"additional","affiliation":[{"name":"St. Jude Children\u2019s Research Hospital, Department of Radiation Oncology, Memphis, TN,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Vadim","family":"Moskvin","sequence":"additional","affiliation":[{"name":"St. Jude Children\u2019s Research Hospital, Department of Radiation Oncology, Memphis, TN,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zuofeng","family":"Li","sequence":"additional","affiliation":[{"name":"University of Florida Proton Therapy Institute"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yian","family":"Guo","sequence":"additional","affiliation":[{"name":"St. Jude Children\u2019s Research Hospital, Department of Biostatistics, Memphis, TN,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yimei","family":"Li","sequence":"additional","affiliation":[{"name":"St. Jude Children\u2019s Research Hospital, Department of Biostatistics, Memphis, TN,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Thomas E","family":"Merchant","sequence":"additional","affiliation":[{"name":"St. Jude Children\u2019s Research Hospital, Department of Radiation Oncology, Memphis, TN,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Austin M","family":"Faught","sequence":"additional","affiliation":[{"name":"St. Jude Children\u2019s Research Hospital, Department of Radiation Oncology, Memphis, TN,"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"266","published-online":{"date-parts":[[2021,4,1]]},"reference":[{"key":"pmbabe835bib1","doi-asserted-by":"publisher","first-page":"1386","DOI":"10.1118\/1.3685447","type":"journal-article","article-title":"The use and QA of biologically related models for treatment planning: short report of the TG-166 of the therapy physics committee of the AAPM","volume":"39","author":"Allen","year":"2012","journal-title":"Med. 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All rights, including for text and data mining, AI training, and similar technologies, are reserved.","name":"copyright_information","label":"Copyright Information"},{"value":"2021-01-25","name":"date_received","label":"Date Received","group":{"name":"publication_dates","label":"Publication dates"}},{"value":"2021-02-19","name":"date_accepted","label":"Date Accepted","group":{"name":"publication_dates","label":"Publication dates"}},{"value":"2021-04-01","name":"date_epub","label":"Online publication date","group":{"name":"publication_dates","label":"Publication dates"}}]}}