S1230
Clinical - Urology
ESTRO 2026
reported outcomes (IPSS, SHIM, EPIC-26) between regimens. The present report provides early six-month outcomes from the completed 500-patient cohort, further clarifying the early-tolerance profile of pelvic UHF + HDRb in high-risk prostate cancer. Material/Methods: The PCS-XI is a non-inferiority, phase 3 RCT involving 11 Canadian institutions in Québec, Ontario and British Columbia. Eligible patients presented prostatic adenocarcinoma of unfavorable intermediate, high or very-high risk. Patients, enrolled between October 2022 and August 2025, were randomized 1:1 to pelvic CF (40-46Gy/20-23 fractions) or pelvic UHF (25Gy/5 fractions delivered on alternate days). Both regimens were preceded by a single-fraction HDRb (15Gy) to the prostate with or without proximal seminal vesicles’ inclusion. Toxicities (CTCAEv5) and patient-reported outcomes (IPSS, SHIM, EPIC-26) were recorded longitudinally. Results: This final cohort analysis expands upon the previously reported interim results and includes 501 patients that have been randomized (CF=251, UHF=250). Median follow-up reached 8.6 months (IQR 2.3) and 8.0 months (IQR 2.4) for CF and UHF, respectively. Baseline characteristics, including Charlson index, PSA, grade group, stage and risk group, were well balanced. Rates of grade ≥ 2 gastrointestinal (GI) and genitourinary (GU) toxicities were comparable. No grade 4 or 5 events occurred. Patient-reported outcomes (IPSS, SHIM, EPIC-26) did not differ significantly at baseline, nor at 3- or 6-month assessments, confirming equivalence in the early trajectory of functional outcomes.
Proffered Paper 2468
Conventional vs Pelvic Ultra-Hypofractionated IMRT with HDR Brachytherapy in Prostate Cancer: Early Outcomes from PCS-XI Complete Cohort(NCT05820633). Francois Fabi 1 , Juanita Crook 2 , Marjorie Joliecoeur 3 , Sarah Rauth 4 , Wayne Koll 5 , Annie Ebacher 6 , Steven Tisseveransinghe 7 , Tamim Niazi 8 , Danny Duplan 9 , Andrée-Anne Bernard 10 , Peter Vavassis 11 , Sindy Magnan 1,12 , William Foster 1,12 , Marie-Anne Froment 1,12 , Eric Vigneault 1,12 , Francois Bachand 1,12 , Bernard Lachance 13 , Louis Archambault 13,12 , Luc Beaulieu 13,12 , Eric Poulin 13,12 , Marie-Claude Lavallée 13 , Sylviane Aubin 13 , Frédérick Lacroix 13 , Damien Carignan 12 , André-Guy Martin 1,12 1 Radiation Oncology, Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Québec, Canada. 2 Radiation Oncology, BC Cancer-Kelowna, Kelowna, Canada. 3 Radiation Oncology, Hôpital Charles LeMoyne, Greenfield Park, Canada. 4 Radiation Oncology, Carlo Fidani Peel Regional Cancer Centre, Mississauga, Canada. 5 Radiation Oncology, RS McLaughlin Durham Regional Cancer Centre, Oshawa, Canada. 6 Radiation Oncology, Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Canada. 7 Radiation Oncology, Hôpital Gatineau, Gatineau, Canada. 8 Radiation Oncology, Jewish General Hospital, McGill University, Montréal, Canada. 9 Radiation Oncology, Hôpital Cité de-de-la-Santé, Laval, Canada. 10 Radiation Oncology, Centre Intégré de Santé et de Services Sociaux du Bas St-Laurent, Rimouski, Canada. 11 Radiation Oncology, Hôpital Maisonneuve-Rosemont, Montréal, Canada. 12 CRCHUQ, Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Québec, Canada. 13 Service of Medical Physics and Radioprotection, Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Québec, Canada Purpose/Objective: Ultra-hypofractionation (UHF) has demonstrated comparable efficacy and safety to conventional fractionation (CF) in prostate-only radiotherapy1. Evidence, however, remains scarce for its application to elective pelvic nodal irradiation when combined with a high-dose-rate prostate brachytherapy (HDRb). The randomized, phase II HOPE trial compared HDRb combined with either pelvic UHF or conventionally fractionated pelvic radiation, demonstrated similar quality-of-life (QoL) and toxicity outcomes between regimens2, yet confirmatory phase III evidence has so far been lacking.The PCS-XI trial (NCT05820633) is a multi-institutional, randomized, non-inferiority phase III study comparing pelvic UHF and CF IMRT, each preceded by a single-fraction HDRb. The planned interim analysis3 (n=142) showed no difference in acute or subacute toxicities and similar patient-
Conclusion: The PCS-XI trial confirms the short-term favorable acute-tolerance profile of pelvic ultra-hypofractionated
Made with FlippingBook - Share PDF online