{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T18:51:14Z","timestamp":1787165474780,"version":"build-2736575974"},"reference-count":32,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2023,10,22]],"date-time":"2023-10-22T00:00:00Z","timestamp":1697932800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cancers"],"abstract":"<jats:p>Purpose: The study evaluates the efficacy of cone-beam computed tomography (CBCT)-based synthetic CTs (sCT) as a potential alternative to verification CT (vCT) for enhanced treatment monitoring and early adaptation in proton therapy. Methods: Seven common treatment sites were studied. Two sets of sCT per case were generated: direct-deformed (DD) sCT and image-correction (IC) sCT. The image qualities and dosimetric impact of the sCT were compared to the same-day vCT. Results: The sCT agreed with vCT in regions of homogeneous tissues such as the brain and breast; however, notable discrepancies were observed in the thorax and abdomen. The sCT outliers existed for DD sCT when there was an anatomy change and for IC sCT in low-density regions. The target coverage exhibited less than a 5% variance in most DD and IC sCT cases when compared to vCT. The Dmax of serial organ-at-risk (OAR) in sCT plans shows greater deviation from vCT than small-volume dose metrics (D0.1cc). The parallel OAR volumetric and mean doses remained consistent, with average deviations below 1.5%. Conclusion: The use of sCT enables precise treatment and prompt early adaptation for proton therapy. The quality assurance of sCT is mandatory in the early stage of clinical implementation.<\/jats:p>","DOI":"10.3390\/cancers15205101","type":"journal-article","created":{"date-parts":[[2023,10,22]],"date-time":"2023-10-22T07:02:53Z","timestamp":1697958173000},"page":"5101","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["The Applications and Pitfalls of Cone-Beam Computed Tomography-Based Synthetic Computed Tomography for Adaptive Evaluation in Pencil-Beam Scanning Proton Therapy"],"prefix":"10.3390","volume":"15","author":[{"given":"Pingfang","family":"Tsai","sequence":"first","affiliation":[{"name":"New York Proton Center, New York, NY 10035, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yu-Lun","family":"Tseng","sequence":"additional","affiliation":[{"name":"Proton Center, Taipei Medical University, Taipei 11031, Taiwan"},{"name":"Department of Radiation Oncology, Taipei Medical University, Taipei 11031, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Brian","family":"Shen","sequence":"additional","affiliation":[{"name":"New York Proton Center, New York, NY 10035, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christopher","family":"Ackerman","sequence":"additional","affiliation":[{"name":"California Protons Center Therapy Center, San Diego, CA 92121, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Huifang A.","family":"Zhai","sequence":"additional","affiliation":[{"name":"New York Proton Center, New York, NY 10035, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francis","family":"Yu","sequence":"additional","affiliation":[{"name":"New York Proton Center, New York, NY 10035, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0867-3694","authenticated-orcid":false,"suffix":"II","given":"Charles B.","family":"Simone","sequence":"additional","affiliation":[{"name":"New York Proton Center, New York, NY 10035, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J. Isabelle","family":"Choi","sequence":"additional","affiliation":[{"name":"New York Proton Center, New York, NY 10035, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nancy Y.","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rafi","family":"Kabarriti","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Montefiore Medical Center, Bronx, NY 10467, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stanislav","family":"Lazarev","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6281-3523","authenticated-orcid":false,"given":"Casey L.","family":"Johnson","sequence":"additional","affiliation":[{"name":"New York Proton Center, New York, NY 10035, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiayi","family":"Liu","sequence":"additional","affiliation":[{"name":"New York Proton Center, New York, NY 10035, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1284-8423","authenticated-orcid":false,"given":"Chin-Cheng","family":"Chen","sequence":"additional","affiliation":[{"name":"New York Proton Center, New York, NY 10035, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haibo","family":"Lin","sequence":"additional","affiliation":[{"name":"New York Proton Center, New York, NY 10035, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,10,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"252","DOI":"10.1016\/j.canrad.2006.05.012","article-title":"Clinical Application of Image-Guided Radiotherapy, IGRT (on the Varian OBI Platform)","volume":"10","author":"Sorcini","year":"2006","journal-title":"Cancer\/Radioth\u00e9rapie"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"284","DOI":"10.1007\/s00066-011-2236-4","article-title":"KV Cone-Beam CT-Based IGRT: A Clinical Review","volume":"187","author":"Lohr","year":"2011","journal-title":"Strahlenther. 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