{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,25]],"date-time":"2026-10-25T00:29:57Z","timestamp":1792888197922,"version":"4.5.0"},"reference-count":35,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2024,2,9]],"date-time":"2024-02-09T00:00:00Z","timestamp":1707436800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Micropos Medical AB (Gothenburg, Sweden)"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Current Oncology"],"abstract":"<jats:p>Background: Stereotactic Body Radiotherapy (SBRT) is as a standard treatment for prostate cancer (PCa). Tight margins and high dose gradients are needed, and the precise localization of the target is mandatory. Our retrospective study reports our experience regarding the evaluation of intrafraction prostate motion during LINAC-based SBRT evaluated with a novel electromagnetic (EM) tracking device. This device consists of an integrated Foley catheter with a transmitter connected to a receiver placed on the treatment table. Methods: We analyzed 31 patients who received LINAC-based SBRT using flattening filter-free (FFF) volumetric modulated arc therapy (VMAT). The patients were scheduled to be treated for primary (n = 27) or an intraprostatic recurrent PCa (n = 4). A simulation CT scan was conducted while the patients had a filled bladder (100\u2013150 cc) and an empty rectum, and an EM tracking device was used. The same rectal and bladder conditions were employed during the treatment. The patients received 36.25 Gy delivered over five consecutive fractions on the whole prostate and 40 Gy on the nodule(s) visible via MRI, both delivered with a Simultaneous Integrated Boost approach. The CTV-to-PTV margin was 2 mm for both the identified treatment volumes. Patient positioning was verified with XVI ConeBeam-CT (CBCT) matching before each fraction. When the signals exceeded a 2 mm threshold in any of the three spatial directions, the treatment was manually interrupted. A new XVI CBCT was performed if this offset lasted &gt;20 s. Results: We analyzed data about 155 fractions. The median and mean treatment times, calculated per fraction, were 10 m31 s and 12 m44 s (range: 6 m36 s\u201365 m28 s), and 95% of the fractions were delivered with a maximum time of 27 m48 s. During treatment delivery, the mean and median number of XVI CBCT operations realized during the treatment were 2 and 1 (range: 0\u201311). During the treatment, the prostate was outside the CTV-to-PTV margin (2 mm), thus necessitating the stoppage of the delivery +\/\u2212 a reacquisition of the XVI CBCT for 11.2%, 8.9%, and 3.9% of the delivery time in the vertical, longitudinal, and lateral direction, respectively. Conclusions: We easily integrated an EM-transmitter-based gating for prostate LINAC-based SBRT into our normal daily workflow. Using this system, a 2 mm CTV-to-PTV margin could be safely applied. A small number of fractions showed a motion exceeding the predefined 2 mm threshold, which would have otherwise gone undetected without intrafraction motion management.<\/jats:p>","DOI":"10.3390\/curroncol31020072","type":"journal-article","created":{"date-parts":[[2024,2,9]],"date-time":"2024-02-09T09:04:01Z","timestamp":1707469441000},"page":"962-974","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Electromagnetic Transmitter-Based Prostate Gating for Dose-Escalated Linac-Based Stereotactic Body Radiation Therapy: An Evaluation of Intrafraction Motion"],"prefix":"10.3390","volume":"31","author":[{"given":"Berardino","family":"De Bari","sequence":"first","affiliation":[{"name":"Radiation Oncology Department, R\u00e9seau Hospitalier Neuch\u00e2telois, CH-2300 La Chaux-de-Fond, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Geoffroy","family":"Guibert","sequence":"additional","affiliation":[{"name":"Medical Physics Department, R\u00e9seau Hospitalier Neuch\u00e2telois, CH-2300 La Chaux-de-Fond, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sabrine","family":"Slimani","sequence":"additional","affiliation":[{"name":"Radiation Oncology Department, R\u00e9seau Hospitalier Neuch\u00e2telois, CH-2300 La Chaux-de-Fond, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yanes","family":"Bashar","sequence":"additional","affiliation":[{"name":"Radiation Oncology Department, R\u00e9seau Hospitalier Neuch\u00e2telois, CH-2300 La Chaux-de-Fond, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Terence","family":"Risse","sequence":"additional","affiliation":[{"name":"Medical Physics Department, R\u00e9seau Hospitalier Neuch\u00e2telois, CH-2300 La Chaux-de-Fond, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nicole","family":"Guisolan","sequence":"additional","affiliation":[{"name":"Radiation Oncology Department, R\u00e9seau Hospitalier Neuch\u00e2telois, CH-2300 La Chaux-de-Fond, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Juliane","family":"Trouillot","sequence":"additional","affiliation":[{"name":"Radiation Oncology Department, R\u00e9seau Hospitalier Neuch\u00e2telois, CH-2300 La Chaux-de-Fond, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jonathan","family":"Abel","sequence":"additional","affiliation":[{"name":"Radiation Oncology Department, R\u00e9seau Hospitalier Neuch\u00e2telois, CH-2300 La Chaux-de-Fond, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Patrick","family":"Weber","sequence":"additional","affiliation":[{"name":"Medical Physics Department, R\u00e9seau Hospitalier Neuch\u00e2telois, CH-2300 La Chaux-de-Fond, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,2,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e17","DOI":"10.1016\/j.ijrobp.2010.10.075","article-title":"Dose-Fractionation Sensitivity of Prostate Cancer Deduced From Radiotherapy Outcomes of 5969 Patients in Seven International Institutional Datasets: A\/b = 1.4 (0.9 \u2212 2.2)Gy","volume":"82","author":"Miralbell","year":"2012","journal-title":"Int. J. Radiat. Oncol. Biol. Phys."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"963","DOI":"10.3109\/0284186X.2012.719635","article-title":"Prostate a\/b Revisited\u2014An Analysis of Clinical Results from 14168 Patients","volume":"51","author":"Dasu","year":"2012","journal-title":"Acta Oncol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"195","DOI":"10.1016\/j.ijrobp.2009.10.008","article-title":"Confirmation of a Low a\/b Ratio for Prostate Cancer Treated by External Beam Radiation Therapy Alone Using a Post-Treatment Repeated-Measures Model for PSA Dynamics","volume":"79","author":"Taylor","year":"2011","journal-title":"Int. J. Radiat. Oncol. Biol. Phys."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"48","DOI":"10.1016\/j.ctrv.2016.08.005","article-title":"Extreme hypofractionation for early prostate cancer: Biology meets technology","volume":"50","author":"Arcangeli","year":"2016","journal-title":"Cancer Treat. Rev."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"553","DOI":"10.1586\/14737140.2014.883282","article-title":"From radiobiology to technology: What is changing in radiotherapy for prostate cancer","volume":"14","author":"Fiorentino","year":"2014","journal-title":"Expert Rev. Anticancer Ther."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"101","DOI":"10.1016\/j.critrevonc.2011.11.009","article-title":"Will SBRT Replace Conventional Radiotherapy in Patients with Low-Intermediate Risk Prostate Cancer? A Review","volume":"84","author":"Arcangeli","year":"2012","journal-title":"Crit. Rev. Oncol. Hematol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"354","DOI":"10.1016\/j.prro.2018.08.002","article-title":"Hypofractionated Radiation Therapy for Localized Prostate Cancer: An ASTRO, ASCO, and AUA Evidence-Based Guideline","volume":"8","author":"Morgan","year":"2018","journal-title":"Pract. Radiat. Oncol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"e188006","DOI":"10.1001\/jamanetworkopen.2018.8006","article-title":"Long-Term Outcomes of Stereotactic Body Radiotherapy for Low-Risk and Intermediate-Risk Prostate Cancer","volume":"2","author":"Kishan","year":"2019","journal-title":"JAMA Netw. Open"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"778","DOI":"10.1016\/j.ijrobp.2019.03.051","article-title":"Stereotactic Body Radiation Therapy for Localized Prostate Cancer: A Systematic Review and Meta-Analysis of Over 6000 Patients Treated On Prospective Studies","volume":"104","author":"Jackson","year":"2019","journal-title":"Int. J. Radiat. Oncol. Biol. Phys."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"385","DOI":"10.1016\/S0140-6736(19)31131-6","article-title":"Ultra-Hypofractionated Versus Conventionally Fractionated Radiotherapy for Prostate Cancer: 5-Year Outcomes of the HYPO-RT-PC Randomised, Non-Inferiority, Phase 3 Trial","volume":"394","author":"Widmark","year":"2019","journal-title":"Lancet"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1308","DOI":"10.1016\/S1470-2045(22)00517-4","article-title":"Intensity-modulated radiotherapy versus stereotactic body radiotherapy for prostate cancer (PACE-B): 2-year toxicity results from an open-label, randomised, phase 3, non-inferiority trial","volume":"23","author":"Tree","year":"2022","journal-title":"Lancet Oncol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"549","DOI":"10.1088\/0031-9155\/60\/2\/549","article-title":"Intra-Fraction Motion of the Prostate Is a Random Walk","volume":"60","author":"Ballhausen","year":"2015","journal-title":"Phys. Med. Biol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"266","DOI":"10.1016\/j.radonc.2012.03.016","article-title":"Evaluation of the respiratory prostate motion with four-dimensional computed tomography scan acquisitions using three implanted markers","volume":"103","author":"Udrescu","year":"2012","journal-title":"Radiother. Oncol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"130","DOI":"10.1002\/acm2.12195","article-title":"Real-Time Intrafraction Prostate Motion During Linac Based Stereotactic Radiotherapy With Rectal Displacement","volume":"18","author":"Legge","year":"2017","journal-title":"J. Appl. Clin. Med. Phys."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"588","DOI":"10.1016\/j.ijrobp.2014.10.049","article-title":"Continuous Monitoring and Intrafraction Target Position Correction During Treatment Improves Target Coverage for Patients Undergoing SBRT Prostate Therapy","volume":"91","author":"Lovelock","year":"2015","journal-title":"Int. J. Radiat. Oncol. Biol. Phys."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"883725","DOI":"10.3389\/fonc.2022.883725","article-title":"Intrafraction Prostate Motion Management during Dose-Escalated Linac-Based Stereotactic Body Radiation Therapy","volume":"7","author":"Panizza","year":"2022","journal-title":"Front. Oncol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"320","DOI":"10.1016\/j.ijrobp.2018.09.023","article-title":"50-Gy Stereotactic Body Radiation Therapy to the Dominant Intraprostatic Nodule: Results From a Phase 1a\/b Trial","volume":"103","author":"Herrera","year":"2019","journal-title":"Int. J. Radiat. Oncol. Biol. Phys."},{"key":"ref_18","first-page":"20180027","article-title":"Stereotactic prostate focal reirradiation therapy for local recurrence: Preliminary results of Hartmann Oncology Radiotherapy Group","volume":"1","author":"Scher","year":"2019","journal-title":"BJR Open"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"180","DOI":"10.1186\/s13014-021-01908-0","article-title":"Treatment Outcome and Compliance to Dose-Intensified Linac-Based SBRT for Unfavorable Prostate Tumors Using a Novel Real-Time Organ- Motion Tracking","volume":"16","author":"Lucchini","year":"2021","journal-title":"Radiat. Oncol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"307","DOI":"10.1016\/j.radonc.2008.08.018","article-title":"High Precision Transponder Localization Using a Novel Electromagnetic Positioning System in Patients With Localized Prostate Cancer","volume":"90","author":"Kindblom","year":"2009","journal-title":"Radiother. Oncol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"244","DOI":"10.1097\/PAS.0000000000000530","article-title":"The 2014 International Society of Urological Pathology (ISUP) Consensus Conference on Gleason Grading of Prostatic Carcinoma: Definition of Grading Patterns and Proposal for a New Grading System","volume":"40","author":"Epstein","year":"2016","journal-title":"Am. J. Surg. Pathol."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1420","DOI":"10.1016\/j.ijrobp.2018.07.2006","article-title":"Daily Versus Weekly Prostate Cancer Image Guided Radiation Therapy: Phase 3 Multicenter Randomized Trial","volume":"102","author":"Bayar","year":"2018","journal-title":"Int. J. Radiat. Oncol. Biol. Phys."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"965","DOI":"10.1016\/j.ijrobp.2004.11.032","article-title":"Increased Risk of Biochemical and Local Failure in Patients With Distended Rectum on the Planning CT for Prostate Cancer Radiotherapy","volume":"62","author":"Tucker","year":"2005","journal-title":"Int. J. Radiat. Oncol. Biol. Phys."},{"key":"ref_24","first-page":"81","article-title":"The role of image-guided radiotherapy in prostate cancer: A systematic review and meta-analysis","volume":"38","author":"Wang","year":"2023","journal-title":"Clin. Transl. Radiat. Oncol."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Bertholet, J., Knopf, A., Eiben, B., McClelland, J., Grimwood, A., Harris, E., Menten, M., Poulsen, P., Nguyen, D.T., and Keall, P. (2019). Real-Time Intrafraction Motion Monitoring in External Beam Radiotherapy. Phys. Med. Biol., 64.","DOI":"10.1088\/1361-6560\/ab2ba8"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1088","DOI":"10.1016\/j.ijrobp.2006.10.026","article-title":"Multi-Institutional Clinical Experience With the Calypso System in Localization and Continuous, Real-Time Monitoring of the Prostate Gland During External Radiotherapy","volume":"67","author":"Kupelian","year":"2007","journal-title":"Int. J. Radiat. Oncol. Biol. Phys."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"N393","DOI":"10.1088\/0031-9155\/54\/17\/N03","article-title":"Tradeoffs of Integrating Real-Time Tracking Into IGRT for Prostate Cancer Treatment","volume":"54","author":"Zhu","year":"2009","journal-title":"Phys. Med. Biol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"336","DOI":"10.1016\/j.radonc.2018.05.031","article-title":"Clinical Feasibility and Positional Stability of an Implanted Wired Transmitter in a Novel Electromagnetic Positioning System for Prostate Cancer Radiotherapy","volume":"128","author":"Braide","year":"2018","journal-title":"Radiother. Oncol."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"10","DOI":"10.1016\/j.ejmp.2018.11.007","article-title":"Localization Accuracy of Two Electromagnetic Tracking Systems in Prostate Cancer Radiotherapy: A Comparison with Fiducial Marker Based Kilovoltage Imaging","volume":"56","author":"Vanhanen","year":"2018","journal-title":"Phys. Med."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"568","DOI":"10.1016\/S0360-3016(02)03008-0","article-title":"Measurement of Intrafractional Prostate Motion Using Magnetic Resonance Imaging","volume":"54","author":"Mah","year":"2002","journal-title":"Int. J. Radiat. Oncol. Biol. Phys."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"640","DOI":"10.1016\/j.clon.2011.12.001","article-title":"Intra- Fraction Motion during Extreme Hypofractionated Radiotherapy of the Prostate Using Pre- and Post-Treatment Imaging","volume":"24","author":"Quon","year":"2012","journal-title":"Clin. Oncol."},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Koike, Y., Sumida, I., Mizuno, H., Shiomi, H., Kurosu, K., Ota, S., Yoshioka, Y., Suzuki, O., Tamari, K., and Ogawa, K. (2018). Dosimetric Impact of Intra-Fraction Prostate Motion Under a Tumour-Tracking System in hypofractionated robotic radiosurgery. PLoS ONE, 13.","DOI":"10.1371\/journal.pone.0195296"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"e388","DOI":"10.1016\/j.prro.2020.04.013","article-title":"Prostate SBRT With Intrafraction Motion Management Using a Novel Linear Accelerator-Based MV-kV Imaging Method","volume":"10","author":"Gorovets","year":"2020","journal-title":"Pract. Radiat. Oncol."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"539","DOI":"10.3389\/fonc.2020.00539","article-title":"Clinical Assessment of Prostate Displacement and Planning Target Volume Margins for Stereotactic Body Radiotherapy of Prostate Cancer","volume":"10","author":"Juarez","year":"2020","journal-title":"Front. Oncol."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"125","DOI":"10.1016\/j.ijrobp.2011.11.047","article-title":"Improved Clinical Outcomes with High-Dose Image Guided Radiotherapy Compared With Non-IGRT for the Treatment of Clinically Localized Prostate Cancer","volume":"84","author":"Zelefsky","year":"2012","journal-title":"Int. J. Radiat. Oncol. Biol. Phys."}],"container-title":["Current Oncology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1718-7729\/31\/2\/72\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T13:57:51Z","timestamp":1760104671000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1718-7729\/31\/2\/72"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,2,9]]},"references-count":35,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2024,2]]}},"alternative-id":["curroncol31020072"],"URL":"https:\/\/doi.org\/10.3390\/curroncol31020072","relation":{},"ISSN":["1718-7729"],"issn-type":[{"value":"1718-7729","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,2,9]]}}}