{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,3]],"date-time":"2026-07-03T11:25:45Z","timestamp":1783077945206,"version":"3.54.6"},"reference-count":38,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,7,3]],"date-time":"2026-07-03T00:00:00Z","timestamp":1783036800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Current Oncology"],"abstract":"<jats:p>MR-guided adaptive radiotherapy (ART) enables daily plan optimization for prostate cancer but is resource-intensive. This study evaluated dosimetric and clinical outcomes following transition from radiation oncologist (RO)-led to radiation therapist (RTT)-led MR-guided ART. All prostate cancer patients treated with MR-guided ART on a 1.5T MR-linac were retrospectively reviewed. Consecutive RO-led (September 2019\u2013November 2021) and RTT-led (April 2022\u2013October 2023) cohorts were compared, excluding the actual transition period. Toxicities (CTCAE v5.0), dose\u2013volume metrics from daily adapted plans, target volume variation, and biochemical recurrence-free survival (BRFS) were analyzed. A total of 166 patients were included (78 RO-led, 88 RTT-led; median follow-up 40 and 35 months). Dosimetric differences between the cohorts were statistically small (&lt;1%). Rates of G2+ GI adverse events were similar across all timepoints. An increase in on-treatment GU events was observed in the RTT-led cohort (G2+ 27% vs. 9%, G3 incidence n = 2 vs. n = 0), likely reflecting higher baseline urinary dysfunction; no post-treatment differences persisted. Early biochemical outcomes were comparable, with 36-month BRFS of 93.5% (RO-led) and 95.0% (RTT-led). RTT-led MR-guided ART achieved comparable dosimetric quality and early biochemical outcomes to RO-led workflows with adverse advents that resolved in the long term. With structured training and a mature practice setting, RTT-led ART represents a scalable model to support future adaptive radiotherapy practice.<\/jats:p>","DOI":"10.3390\/curroncol33070398","type":"journal-article","created":{"date-parts":[[2026,7,3]],"date-time":"2026-07-03T07:59:47Z","timestamp":1783065587000},"page":"398","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Transition from Oncologist- to Therapist-Led MRI-Guided Ultra-Hypofractionated Adaptive Prostate Radiation Therapy: Evaluation of Early Clinical Outcomes"],"prefix":"10.3390","volume":"33","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-5525-1498","authenticated-orcid":false,"given":"Amanda","family":"Moreira","sequence":"first","affiliation":[{"name":"Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C4, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tara","family":"Rosewall","sequence":"additional","affiliation":[{"name":"Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C4, Canada"},{"name":"Department of Radiation Oncology, University of Toronto, Toronto, ON M5G 2M9, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jennifer","family":"Dang","sequence":"additional","affiliation":[{"name":"Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C4, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aran","family":"Kim","sequence":"additional","affiliation":[{"name":"Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C4, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna T.","family":"Santiago","sequence":"additional","affiliation":[{"name":"Biostatistics Core, University Health Network, Toronto, ON M5G 1X6, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8327-794X","authenticated-orcid":false,"given":"Aruz","family":"Mesci","sequence":"additional","affiliation":[{"name":"Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C4, Canada"},{"name":"Department of Radiation Oncology, University of Toronto, Toronto, ON M5G 2M9, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Enrique","family":"Gutierrez","sequence":"additional","affiliation":[{"name":"Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C4, Canada"},{"name":"Department of Radiation Oncology, University of Toronto, Toronto, ON M5G 2M9, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew","family":"Bayley","sequence":"additional","affiliation":[{"name":"Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C4, Canada"},{"name":"Department of Radiation Oncology, University of Toronto, Toronto, ON M5G 2M9, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew","family":"McPartlin","sequence":"additional","affiliation":[{"name":"Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C4, Canada"},{"name":"Department of Radiation Oncology, University of Toronto, Toronto, ON M5G 2M9, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rachel M.","family":"Glicksman","sequence":"additional","affiliation":[{"name":"Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C4, Canada"},{"name":"Department of Radiation Oncology, University of Toronto, Toronto, ON M5G 2M9, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alejandro","family":"Berlin","sequence":"additional","affiliation":[{"name":"Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C4, Canada"},{"name":"Department of Radiation Oncology, University of Toronto, Toronto, ON M5G 2M9, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0873-0254","authenticated-orcid":false,"given":"Jeff","family":"Winter","sequence":"additional","affiliation":[{"name":"Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C4, Canada"},{"name":"Department of Radiation Oncology, University of Toronto, Toronto, ON M5G 2M9, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Winnie","family":"Li","sequence":"additional","affiliation":[{"name":"Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C4, Canada"},{"name":"Department of Radiation Oncology, University of Toronto, Toronto, ON M5G 2M9, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3815-7703","authenticated-orcid":false,"given":"Peter","family":"Chung","sequence":"additional","affiliation":[{"name":"Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C4, Canada"},{"name":"Department of Radiation Oncology, University of Toronto, Toronto, ON M5G 2M9, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"191","DOI":"10.1016\/j.eururo.2023.04.021","article-title":"2022 Update on Prostate Cancer Epidemiology and Risk Factors\u2014A Systematic 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