{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,21]],"date-time":"2026-10-21T20:54:28Z","timestamp":1792616068595,"version":"4.5.0"},"reference-count":42,"publisher":"IOP Publishing","issue":"5","license":[{"start":{"date-parts":[[2021,2,25]],"date-time":"2021-02-25T00:00:00Z","timestamp":1614211200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2021,2,25]],"date-time":"2021-02-25T00:00:00Z","timestamp":1614211200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/iopscience.iop.org\/info\/page\/text-and-data-mining"}],"funder":[{"DOI":"10.13039\/501100000289","name":"Cancer Research UK","doi-asserted-by":"crossref","award":["C33589\/A19727"],"award-info":[{"award-number":["C33589\/A19727"]}],"id":[{"id":"10.13039\/501100000289","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100000272","name":"National Institute for Health Research","doi-asserted-by":"crossref","award":["HCS DRF-2014-05-005"],"award-info":[{"award-number":["HCS DRF-2014-05-005"]}],"id":[{"id":"10.13039\/501100000272","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":[[2021,3,7]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Target volume delineation uncertainty (DU) is arguably one of the largest geometric uncertainties in radiotherapy that are accounted for using planning target volume (PTV) margins. Geometrical uncertainties are typically derived from a limited sample of patients. Consequently, the resultant margins are not tailored to individual patients. Furthermore, standard PTVs cannot account for arbitrary anisotropic extensions of the target volume originating from DU. We address these limitations by developing a method to measure DU for each patient by a single clinician. This information is then used to produce PTVs that account for each patient\u2019s unique DU, including any required anisotropic component. We do so using a two-step uncertainty evaluation strategy that does not rely on multiple samples of data to capture the DU of a patient\u2019s gross tumour volume (GTV) or clinical target volume. For simplicity, we will just refer to the GTV in the following. First, the clinician delineates two contour sets; one which bounds all voxels believed to have a probability of belonging to the GTV of 1, while the second includes all voxels with a probability greater than 0. Next, one specifies a probability density function for the true GTV boundary position within the boundaries of the two contours. Finally, a patient-specific PTV, designed to account for all systematic errors, is created using this information along with measurements of the other systematic errors. Clinical examples indicate that our margin strategy can produce significantly smaller PTVs than the van Herk margin recipe. Our new radiotherapy target delineation concept allows DUs to be quantified by the clinician for each patient, leading to PTV margins that are tailored to each unique patient, thus paving the way to a greater personalisation of radiotherapy.<\/jats:p>","DOI":"10.1088\/1361-6560\/abe029","type":"journal-article","created":{"date-parts":[[2021,1,26]],"date-time":"2021-01-26T17:32:32Z","timestamp":1611682352000},"page":"055024","update-policy":"https:\/\/doi.org\/10.1088\/crossmark-policy","source":"Crossref","is-referenced-by-count":14,"title":["New target volume delineation and PTV strategies to further personalise radiotherapy"],"prefix":"10.1088","volume":"66","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7442-0698","authenticated-orcid":false,"given":"David","family":"Bernstein","sequence":"first","affiliation":[{"name":"Joint Department of Physics, The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, Fulham Road, London, SW3 6JJ,"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexandra","family":"Taylor","sequence":"additional","affiliation":[{"name":"Gynaecology Unit, Royal Marsden NHS Foundation Trust, Fulham Road, London, SW3 6JJ,"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Simeon","family":"Nill","sequence":"additional","affiliation":[{"name":"Joint Department of Physics, The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, SM2 5PT,"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Uwe","family":"Oelfke","sequence":"additional","affiliation":[{"name":"Joint Department of Physics, The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, SM2 5PT,"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"266","published-online":{"date-parts":[[2021,2,25]]},"reference":[{"key":"pmbabe029bib1","doi-asserted-by":"publisher","first-page":"118","DOI":"10.1016\/j.radonc.2017.08.012","type":"journal-article","article-title":"Evaluation of high dose volumetric CT to reduce inter-observer delineation variability and PTV margins for prostate cancer radiotherapy","volume":"125","author":"Alasti","year":"2017","journal-title":"Radiother. 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Published on behalf of Institute of Physics and Engineering in Medicine by IOP Publishing Ltd","name":"copyright_information","label":"Copyright Information"},{"value":"2020-11-15","name":"date_received","label":"Date Received","group":{"name":"publication_dates","label":"Publication dates"}},{"value":"2021-01-26","name":"date_accepted","label":"Date Accepted","group":{"name":"publication_dates","label":"Publication dates"}},{"value":"2021-02-25","name":"date_epub","label":"Online publication date","group":{"name":"publication_dates","label":"Publication dates"}}]}}