ESTRO 2025 - Abstract Book

S398

Brachytherapy - Urology

ESTRO 2025

Keywords: HDR monotherapy, Prostate cancer,Long-term outcome

References:

1. Hoskin P, Rojas A, Ostler P, et al. Single–dose high-dose-rate brachytherapy versus two and three fractions for locally advanced prostate cancer. Radiotherapy and Oncology. 2024 Oct;199:110426. doi:10.1016/j.radonc.2024.110426 2. Hudson JM, Loblaw A, McGuffin M, et al. Prostate high dose-rate brachytherapy as monotherapy for low and intermediate-risk prostate cancer: Efficacy results from a randomized phase II clinical trial of one fraction of 19 gy or two fractions of 13.5 gy: A 9-year update. Radiotherapy and Oncology. 2024 Sept;198:110381. doi:10.1016/j.radonc.2024.110381

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Digital Poster LONG TERM OUTCOME AFTER LOW-DOSE-RATE BRACHYTHERAPY FOR PROSTATE CANCER IN ONE OF THE LARGEST PATIENT COHORTS WORLDWIDE: TRENTO HOSPITAL EXPERIENCE Sergio Fersino 1 , Francesco Ziglio 2 , Maria Andolina 1 , Laura Bandera 1 , Anna Delana 2 , Fiorenza De Rose 1 , Lucia Di Brina 1 , Patrizia Ferrazza 1 , Sara Lucidi 1 , Elena Magri 1 , andrea martignano 2 , Loris Menegotti 2 , Mario Petrazzuoli 3 , Annalisa Trianni 2 , Dea Veshaj 1 , Valentina Vanoni 1 , Salvatore Mussari 1 1 Radiation Oncology, APSS, Trento, Italy. 2 Medical Physics, APSS, Trento, Italy. 3 Radiation Oncology, A.O.U Federico II, Napoli, Italy Purpose/Objective: To report long-term efficacy and toxicity for a single-institution cohort of patients treated with permanent implant low-dose-rate prostate brachytherapy (LDR-BT) Material/Methods: From May 2000 to September 2023, 1002 patients were treated for localized prostate cancer (PC) in a single Institution using LDR-BT. A subset of 921 patients were treated with iodine-125 ( 125 I) as monotherapy to 145 Gy for low-risk (59.4%), intermediate-risk (39.4%) or – infrequently -high- risk (1.2%) prostate cancer Survival with freedom from failure (FFF), disease-specific survival (DSS) and overall survival (OS) were estimated using the Kaplan–Meier method. Log-rank test and multivariable Cox regression were used to evaluate the relationship of covariates with outcome. Acute and late genito-urinary (GU) and gastro-intestinal (GI) toxicities were reviewed retrospectively according to a modified Common Terminology Criteria for Adverse Events 5.0 scale. Results: The median age of the patients was 67 years at implant date and median follow-up was 95 months. At 10 years, 329 patients were still alive/at risk. The overall rates for FFF, DSS and OS were 91%, 99%, 88% at median follow-up, 88%, 99% and 85% at 10 years and 77%, 96%, and 54% at 20 years, respectively. At multivariate analysis, dosimetric parameters related to target coverage at postplanning dosimetry evaluation (D90 and V100) showed a significant correlation with FFF. The overall rates of late grade ≥ 3 GU and GI toxicity were 3.6% and 0.3%, respectively.