ESTRO 2024 - Abstract Book

S2594

Clinical - Urology

ESTRO 2024

This study shows that SBRT is a safe and well tolerated treatment option for organ-confined PCa in an unselected patients’ population. According to our findings, stringent selection criteria are not mandatory for prostate SBRT, provided that a careful protocol for patient preparation and monitoring is implemented. Long term follow-up is needed to confirm these results.

Keywords: prostate cancer, SBRT, toxicity

2951

Digital Poster

Reirradiation with SBRT in Patients with Locally Recurrent Prostate Cancer.

Gustavo Alberto Ferraris 1,2 , Ariel Matias Gomez Palacios 1,2 , Pablo Andrada 3 , Gabriel Lazcano Alvarez 4,5 , Tomas Walter Martin 4 , Ofelia Perez Conci 1,2 , Belen Raiden 1,2 , Lucas Caussa 1 , Diego Fernandez 1 , Luciana Brun 1 , Delfina Batisti 3 , Andrea Pozo 3 , Maria Fernanda Diaz Vazquez 1,2 , Carmen Castro 3 , Jose Solis Campos 4,5 2 Universidad Católica de Córdoba, Radioterapia, Cordoba, Argentina. 3 Hospital Aleman, Radioterapia, Buenos Aires, Argentina. 4 Universidad de Valparaiso, Radioterapia, Valparaiso, Chile. 5 Hospital Carlos Van Buren, Radioterapia, Valparaiso, Chile 1 Centro Radioterapia Dean Funes, Radioterapia, Cordoba, Argentina.

Purpose/Objective:

Up to 47% of localized prostate cancer (PC) patients treated with external beam radiotherapy (EBRT) eventually develop local recurrence. However, the management of locally recurrent prostate cancer after radiotherapy remains a subject of debate. There is a growing interest in the use of stereotactic body reirradiation (rSBRT), with promising oncological outcomes and a manageable toxicity profile. The objective of this study is to determine the clinical outcomes and toxicities of patients with locally recurrent PC who received rSBRT.

Material/Methods:

This retrospective multicenter study collected data from 45 patients treated for locally recurrent prostate cancer from January 2017 to September 2023. Patients underwent rSBRT with Linear Accelerators with IGRT capabilities administered to intraprostatic or macroscopic recurrences within the prostatic bed. The administered dose ranged between 30-36.25 Gy in 5 fractions. All patients were staged using F-Choline or Ga-PSMA PET scans. Data analysis was performed using IBM SPSS version 26.0. Kaplan-Meier curves were generated for survival analysis, and Cox regression was used for categorical variable analysis. Toxicity was assessed according to CTCAE v.4.

Results:

Ninety-seven point seven percent (97.7%) of the patients previously received external beam radiotherapy, with only one patient having undergone brachytherapy. The mean EQD2 was of 73 Gy (range, 60 to 88 Gy). Thirty percent