{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,2]],"date-time":"2026-04-02T04:25:53Z","timestamp":1775103953115,"version":"3.50.1"},"reference-count":31,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2022,8,31]],"date-time":"2022-08-31T00:00:00Z","timestamp":1661904000000},"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>Purpose: Determine the time-dependent magnitude of intrafraction prostate displacement and a cutoff for the tracking decision. Methods: Nine patients with localized prostate cancer were treated with ultra-hypofractionated radiotherapy (CyberKnife) with fiducial markers. Exact tract kV\/kV imaging was used with an average interval of 19\u201392 s. A Gaussian distribution was calculated for the x-, y-, and z-directions (\u03c3x,y,z). The variation of prostate motion (\u03bc\u03c3) was obtained by averaging the patients\u2019 specifics, and the safety margin was calculated to be MAB = WYm + WBSs. Results: The calculated PTV safety margins were as follows: at 40 s: 0.55 mm (L\/r), 0.85 mm (a\/p), and 1.05 mm (s\/i); at 60 s: 0.9 mm (L\/r), 1.35 mm (a\/p), and 1.55 mm (s\/i); at 100 s: 1.5 mm (L\/r), 2.3 mm (a\/p), and 2.6 mm (s\/i); at 150 s: 1.9 mm (L\/r), 3.1 mm (a\/p), and 3.6 mm (s\/i); at 200 s: 2.2 mm (L\/r), 3.8 mm (a\/p), and 4.2 mm (s\/i); and at 300 s: 2.6 mm (L\/r), 5.3 mm (a\/p), and 5.6 mm (s\/i). A tracking cutoff of 2.5 min seemed reasonable. In order to achieve an accuracy of &lt; 1 mm, tracking with &lt; 50 s intervals was necessary. Conclusions: For ultra-hypofractionated radiotherapy of the prostate with treatment times &gt; 2.5 min, intrafraction motion management is recommended.<\/jats:p>","DOI":"10.3390\/curroncol29090496","type":"journal-article","created":{"date-parts":[[2022,8,31]],"date-time":"2022-08-31T23:53:21Z","timestamp":1661990001000},"page":"6314-6324","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Intrafraction Prostate Motion Management for Ultra-Hypofractionated Radiotherapy of Prostate Cancer"],"prefix":"10.3390","volume":"29","author":[{"given":"Christoph","family":"Oehler","sequence":"first","affiliation":[{"name":"Department of Radiation Oncology, Hospital Winterthur, 8400 Winterthur, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nina","family":"Roehner","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Hirslanden Zurich, 8032 Zurich, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marcin","family":"Sumila","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Hirslanden Zurich, 8032 Zurich, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"J\u00fcrgen","family":"Curschmann","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Hirslanden Zurich, 8032 Zurich, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fabrizio","family":"Storelli","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Hirslanden Zurich, 8032 Zurich, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4359-7735","authenticated-orcid":false,"given":"Daniel Rudolf","family":"Zwahlen","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Hospital Winterthur, 8400 Winterthur, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Uwe","family":"Schneider","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Hirslanden Zurich, 8032 Zurich, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,8,31]]},"reference":[{"key":"ref_1","unstructured":"NIH (2022, August 20). 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