ESTRO 2025 - Abstract Book

S1928

Clinical - Urology

ESTRO 2025

Conclusion: A pragmatic trial investigating the addition of MD-SBRT to SoC for disease control both in de novo and recurrent omHSPC patients is feasible. The characteristics of the first 50 patients indicate that the results will be generalizable for both patient cohorts.

Keywords: SBRT, oligo-metastatic, prostate cancer

References: 1.Ost P, Reynders D, Decaestecker K, et al. Surveillance or Metastasis-Directed Therapy for Oligometastatic Prostate Cancer Recurrence: A Prospective, Randomized, Multicenter Phase II Trial. J Clin Oncol. 2018;36(5):446-53. 2.Rowe SP, Pienta KJ, Pomper MG, et al. PSMA-RADS Version 1.0: A Step Towards Standardizing the Interpretation and Reporting of PSMA-targeted PET Imaging Studies. Eur Urol. 2018;73(4):485-7. 3.Attard G, Murphy L, Clarke NW, et al. Abiraterone acetate and prednisolone with or without enzalutamide for high risk non-metastatic prostate cancer: a meta-analysis of primary results from two randomised controlled phase 3 trials of the STAMPEDE platform protocol. Lancet. 2022;399(10323):447-60.

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Digital Poster High-risk localized prostate cancer treated with risk-adapted intensification therapy: Clinical impact of radiation dose Almudena Zapatero 1 , Carmen Martin de Vidales 1 , Maria Roch 2 , Pablo Castro-Tejero 2 , Laura Zaragoza 1 , Sara Carroceda 1 , Margarita Casado 1 , Alexandra E Stoica 1 , Feliciano Garcia-Vicente 3,4 1 Radiation Oncology, Hospital Universitario de La Princesa, Instituto de Investigsción Sanitaria, Madrid, Spain. 2 Medical Physics, Hospital Universitario de La Princesa, Instituto de Investigsción Sanitaria, Madrid, Spain. 3 Medical Physics, Hospital Universitario de La Princesa, Madrid, Spain. 4 Medical Physics, Hospital Universitario Ramón y Cajal, Madrid, Spain Purpose/Objective: Management of high-risk prostate cancer (HRPCa) remains a matter of continuous debate. This study aimed to evaluate 10 years outcome, patterns of failure and clinical impact of treatment factors in a prospective cohort of HRPCa patients treated with risk-adapted intensification therapy at a single institution. Material/Methods: A retrospective analysis was conducted on a prospective cohort of 424 consecutive HRPCa patients defined by NCCN criteria, with a minimum follow-up (FU) of 5 years. All patients were treated with external beam radiotherapy (EBRT) as part of a dose-intensification institutional program. The median RT dose to the prostate was 79.2 Gy (interquartile range [IQR] 74.9-80.3). Short term androgen deprivation therapy ADT (STADT) and long term ADT (LTADT) were administered in 56 (13%) and 350 (83%) of patients respectively. Kaplan-Meier curves were used to calculate overall survival (OS). Cumulative incidence of biochemical failure (BF), distant metastasis (DM), and cause specific survival (CSS) were estimated using competing risk regression. Multivariate Cox regression analysis (MVA) was conducted to determine the association between therapeutic and clinical factors and outcomes. Statistical analyses were performed using R version 4.3.2. Results: The median patient age was 69 years (IQR 65-72) and the median FU was 118 months (IQR 88.0-135.0). At the time of analysis , 54 out of 424 (13%) patients have died. The primary cause of death was cardiovascular disease in 16 patients (3.7%), PCa in 15 patients (3.5%), and other neoplasms in 9 (2%). Biochemical failure (nadir + 2) occurred in 101 patients (24%), with a median time to failure of 112 months (IQR 80 – 130). Distant metastases developed in 41 patients (9.7%), with a median time to event of 117.5 months (IQR 86 – 135). At 10 years, Kaplan-Meier estimated OS