Dosimetric Impact of Intrafraction Prostate Motion in Dose Escalated Linac-Based SBRTRead article
Dosimetric Impact of Intrafraction Prostate Motion in Dose Escalated Linac-Based SBRT
D. Panizza,1,2 V. Faccenda,1,3 R. Lucchini,2,4 M.C. Daniotti,3 S. Trivellato,1 P. Caricato,1,3 S. Arcangeli,2,4 and E. De Ponti, 1,2;
1 ASST Monza – Medical Physics Department, Monza, Italy, 2 University of Milan Bicocca – School of Medicine and Surgery, Milan, Italy, 3 University of Milan – Department of Physics, Milan, Italy, 4 ASST Monza – Department of Radiation Oncology, Monza, Italy
Purpose/Objective(s)The aim of this study was to investigate the impact of observed intrafraction prostate motion on dose metrics and the effect of beam gating and motion correction using a novel electromagnetic (EM) tracking device in dose-escalated Linac-based SBRT.
ConclusionOur findings showed that the majority of the observed prostate motion was modest; however, there were a non-insignificant number of fractions with motion exceeding the predetermined threshold. The current CTV to PTV margins, the robustness of original treatment plans, and the fast FFF beams delivery led to minimal degradations of dose metrics for the target and OARs in both cases. Anyway, real-time monitoring with beam gating and motion correction ensured superior results and are recommended in dose-escalated prostate SBRT.
Intrafraction Prostate Motion Management during Dose-Escalated Linac-Based SBRTRead article
D. Panizza, V. Faccenda, R. Lucchini, M.C. Daniotti, S. Trivellato, P. Caricato, S. Arcangeli and E. De Ponti
Published in International Journal of Radiation Oncology, VOLUME 114, ISSUE 3, SUPPLEMENT , E570-E571, NOVEMBER 01, 2022
Purpose/Objective(s)This study reports the first clinical experience worldwide using a novel electromagnetic (EM) tracking device for intrafraction prostate motion management during dose-escalated Linac-based stereotactic body radiation therapy SBRT
ConclusionEM real-time tracking was successfully implemented for intrafraction motion management during dose-escalated prostate SBRT. Results showed that most of the observed displacements were < 2 mm in any direction; however, there were a non-insignificant number of fractions with motion exceeding the predefined threshold, which would have otherwise gone undetected without intrafraction motion management.
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 trialRead article
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
Alison C Tree, Peter Ostler, Hans van der Voet, William Chu, Andrew Loblaw, Daniel Ford, Shaun Tolan, Suneil Jain, Alexander Martin, John Staffurth, John Armstrong, Philip Camilleri, Kiran Kancherla, John Frew, Andrew Chan, Ian S Dayes, Aileen Duffton, Douglas H Brand, Daniel Henderson, Kirsty Morrison, Stephanie Brown, Julia Pugh, Stephanie Burnett, Muneeb Mahmud, Victoria Hinder, Olivia Naismith, Emma Hall*, Nicholas van As*, on behalf of the PACE Trial Investigators
Localised prostate cancer is commonly treated with external beam radiotherapy and moderate hypofractionation is non-inferior to longer schedules. Stereotactic body radiotherapy (SBRT) allows shorter treatment courses without impacting acute toxicity. We report 2-year toxicity findings from PACE-B, a randomised trial of conventionally fractionated or moderately hypofractionated radiotherapy versus SBRT
We enrolled and randomly assigned 874 men between Aug 7, 2012, and Jan 4, 2018 (441 to CRT and 433 to SBRT). In this analysis, 430 patients were analysed in the CRT group and 414 in the SBRT group; a total of 844 (97%) of 874 randomly assigned patients. At 24 months, RTOG grade 2 or worse genitourinary toxicity was seen in eight (2%) of 381 participants assigned to CRT and 13 (3%) of 384 participants assigned to SBRT (absolute difference 1·3% [95% CI –1·3 to 4·0]; p=0·39); RTOG grade 2 or worse gastrointestinal toxicity was seen in 11 (3%) of 382 participants
in the CRT group versus six (2%) of 384 participants in the SBRT group (absolute difference –1·3% [95% CI –3·9 to 1·1]; p=0·32). No serious adverse events (defined as RTOG grade 4 or worse) or treatment-related deaths were reported within the analysis timeframe.
In the PACE-B trial, 2-year RTOG toxicity rates were similar for five fraction SBRT and conventional schedules of radiotherapy. Prostate SBRT was found to be safe and associated with low rates of side-effects. Biochemical outcomes are awaited.
Intrafraction Prostate Motion Management During Dose-Escalated Linac-Based Stereotactic Body Radiation TherapyRead article
Denis Panizza 1,2*, Valeria Faccenda 1,3, Raffaella Lucchini 2,4, Martina Camilla Daniotti 1,3, Sara Trivellato1 , Paolo Caricato 1,3, Valerio Pisoni 4, Elena De Ponti 1,2 and Stefano Arcangeli 2,4
1 Medical Physics Department, ASST Monza, Monza, Italy, 2 School of Medicine and Surgery, University of Milan Bicocca, Milan, Italy, 3 Department of Physics, University of Milan, Milan, Italy, 4 Radiation Oncology Department, ASST Monza, Monza, Italy
Extreme hypofractionation requires tight planning margins, high dose gradients, and strict adherence to planning criteria in terms of patient positioning and organ motion mitigation. This study reports the first clinical experience worldwide using a novel electromagnetic (EM) tracking device for intrafraction prostate motion management during dose-escalated linac-based stereotactic body radiation therapy (SBRT).
EM real-time tracking was successfully implemented for intrafraction motion management during dose-escalated prostate SBRT. Results showed that most of the observed displacements were < 2 mm in any direction; however, there were a non insignificant number of fractions with motion exceeding the predefined threshold, which would have otherwise gone undetected without intrafraction motion management.
Treatment outcome and compliance to dose-intensifed linac-based SBRT for unfavorable prostate tumors using a novel real-time organ-motion trackingRead article
Rafaella Lucchini1,2, Denis Panizza1,3, Riccardo Ray Colciago1,2* , Veronica Vernier1, Martina Camilla Daniotti4,Valeria Faccenda3,5 and Stefano Arcangeli1,2
To report preliminary data on treatment outcome and compliance to dose-intensified organ sparing SBRT for prostate cancer using a novel electromagnetic transmitter-based tracking system (RayPilot® System) to account for intra-fractional organ motion.
Our preliminary fndings show that dose intensifed SBRT for unfavorable prostate tumors does not come at the cost of an increased toxicity, provided that a reliable technique for real time prostate monitoring is ensured. Fast FFF beams contributed to reduce intra-fractional motion. These observations need to be confrimed on a larger scale and a longer follow up.