194 - Daily Online Adaptive Recontouring for Prostate Cancer Using 1.5 Tesla Magnetic Resonance Image Guidance (MRgRT) Improves Patient Reported Urinary Symptoms, A Prospective, International, Observational Cohort Study (NCT04075305)
Presenter(s)
W. A. Hall1, F. Raaijmakers2, A. Tree3, J. P. Christodouleas4, J. Van der Voort vanZyp5, U. van der Heide6, F. J. Pos7, P. Westhoff8, A. Choudhury9, D. Vesprini10, S. Hafeez11, E. Hoffmann12, M. W. Straza Jr13, P. Jeene14, J. M. Longo15, C. D. Fuller16, F. Alongi17, T. Schytte18, J. M. Westerhoff19, E. Hall20, L. A. Daamen21, and H. Verkooijen22; 1Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI, 2UMC Utrecht, Utrecht, Netherlands, 3The Royal Marsden and The Institute of Cancer Research National Institute for Health Research Biomedical Research Centre, London, United Kingdom, 4Elekta, Stockholm, Sweden, 5UMC, Utrecht, Netherlands, 6Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, Netherlands, 7The Netherlands Cancer Institute, Amsterdam, Netherlands, 8Radboud University Medical Center, Nijmegen, Netherlands, 9Division of Cancer Sciences, University of Manchester, Manchester, United Kingdom, 10Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada, 11The Institute of Cancer Research, Division of Radiotherapy and Imaging, London, United Kingdom, 12Universitätsklinikum Tübingen, Tubingen, Germany, 13Department of Radiation Oncology, Froedtert & the Medical College of Wisconsin, Milwaukee, WI, 14Radiotherapiegroep, Deventer, Netherlands, 15Medical College of Wisconsin, Milwaukee, WI, 16Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 17Department of Advanced Radiation Oncology, IRCSS "Sacro Cuore Don Calabria Hospital" Cancer Care Center, Negrar di Valpolicella (VR), Italy, 18Department of Oncology, Odense University Hospital, Odense, Denmark, 19Department of Radiotherapy, University Medical Center Utrecht, Utrecht, Netherlands, 20The Institute of Cancer Research, London, United Kingdom, 21Department of Radiation Oncology, University Medical Center Utrecht, Utrecht, Netherlands, 22University Medical Center Utrecht, Utrecht, Netherlands
Purpose/Objective(s): Adaptive radiation therapy (RT) is becoming more common. Limited prospective data exists evaluating patient reported outcomes (PROs) with this new technique. We prospectively collected PROs and compared two different treatment strategies in patients undergoing MRgRT for prostate cancer. We hypothesized that daily adaptive recontouring would improve PROs for urinary symptoms, bowel symptoms and sexual functioning.
Materials/Methods: Patients were consented to the The Multiple OutcoMe EvaluatioN of radiation Therapy Using the MR-linac Study (MOMENTUM, NCT04075305) across 12 institutions. Patients meeting inclusion criteria were treated curatively for prostate cancer using 5 fraction stereotactic ablative body radiation (SABR). Two different treatment techniques were used, adapt to shape (ATS) which involves daily recontouring of normal structures or adapt to position (ATP) which does not include daily re-contouring. Patients were unaware of the treatment strategy. The EORTC QLQ C-30 and prostate-specific QLQ PR-25 were completed at baseline, 3, 6, 12, and 24 months. The change in PROs score with respect to baseline were analyzed in a subset of patients treated with ATS and ATP after propensity score matching on risk category, hormone treatment, and reference plan dose-volume-histograms (DVH) for the rectum and bladder. A linear mixed-effects model was used, and results were presented as a difference of mean differences with corresponding 95% confidence interval (CI). A p-value < 0.05 was considered statistically significant.
Results: 1,373 patients were prospectively enrolled from May 2019 to July 2024, 1,054 and 319 were treated with daily recontouring (ATS) and without daily recontouring (ATP) technique, respectively. Median patient age was 71 years. Most patients were categorized as intermediate NCCN risk (93%), median PSA was 7.76 ng/ml, and 16% of the patients received hormonal therapy. Rectal and bladder planning DVHs were available for 86% of patients. 1,181 (86%) patients had PRO scores available. All ATP patients with PROs (n=315) were propensity matched to 315 ATS patients, using reference plan rectal and bladder DVHs in the matching. Patients without daily recontouring (ATP) reported significantly higher increase in scores for urinary symptoms at 3 (Difference -4.4, 95% CI -7.78 to -1.11), 6 (-3.61, 95% CI -7.0 to -0.21) and 12 (-6.6, 95% CI -10.3 to -2.92) months following RT, all p<0.05. Bowel symptoms and sexual functioning showed no significant differences.
Conclusion: Patients with prostate cancer treated with SABR who underwent daily MRI-guided online adaptive recontouring (ATS) had a statistically significant lower increase on PRO urinary symptoms (i.e. less urinary bother) as compared to those without daily recontouring (ATP). To our knowledge, these data represent the highest level of evidence reflecting the benefit of daily online adaptive recontouring on PROs in the treatment of patients with prostate cancer.