ESTRO 2024 - Abstract Book

S2402

Clinical - Urology

ESTRO 2024

Keywords: prostate, salvage radiotherapy, late toxicity

1147

Poster Discussion

Improved biochemical outcome in salvage radiotherapy with pretreatment MRI: a case-control analysis.

Letizia Cavallini 1,2 , Caterina Gaudiano 3 , Beniamino Corcioni 3 , Lorenzo Bianchi 1,4 , Riccardo Schiavina 1,4 , Eugenio Brunocilla 1,4 , Gabriella Macchia 5 , Francesco Deodato 5,6 , Erika Galietta 1,2 , Filippo Mammini 1,2 , Silvia Paolinelli 1,2 , Viola Laghi 1,2 , Elena Natoli 1,2 , Alessandra D'Alterio 1,2 , Giorgio Coco 1,2 , Silvia Bisello 7 , Alessandra Arcelli 2 , Silvia Cammelli 1,2 , Alessio Giuseppe Morganti 1,2 , Maria Ntreta 2 1 Department of Medical and Surgical Sciences (DIMEC), Alma Mater Studiorum University of Bologna, Bologna, Italy. 2 Radiation Oncology, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy. 3 Department of Radiology, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy. 4 Division of Urology, IRCCS Azienda Ospedaliero Universitaria di Bologna, Bologna, Italy. 5 Radiation Oncology Unit, Gemelli Molise-Hospital-Università Cattolica del Sacro Cuore, Campobasso, Italy. 6 Istituto di Radiologia, Università Cattolica del Sacro Cuore, Roma, Italy. 7 Radiation Oncology, Azienda Ospedaliero-Universitaria Ospedali Riuniti di Ancona, Ancona, Italy

Purpose/Objective:

Current international guidelines recommend choline-PET or PSMA-PET in patients with prostate cancer referred for salvage radiotherapy (sRT) to rule out nodal or hematogenous metastases. However, in our centers, we tested the efficacy of pelvic mpMRI in detecting local-regional relapses and, therefore, to optimize sRT. This analysis aims to compare two matched cohorts of patients who underwent or did not undergo mpMRI before sRT regarding biochemical relapse-free survival.

Material/Methods:

One hundred seventy-six patients from three centers were included in this study. Patients in the two cohorts were matched according to PSA before SRT (<0.2; 0.2-0.5; 0.5-1.0; >1.0 ng/ml), pathological tumor stage, ISUP grade (1, 2, 3, 4, 5), prophylactic nodal irradiation, and adjuvant androgen deprivation therapy. Kaplan-Meier survival curves were compared using the log-rank test. This analysis is part of a multicenter observational study approved by the ethics committees of the participating centers.

Results:

Macroscopic local-regional relapse was identified in 54/88 of patients (61.4%) undergoing pelvic mpMRI. Therefore, these patients were treated with a median total dose of 70.4 Gy (range: 66-72.6), while patients without mpMRI or negative mpMRI received a median total dose of 66 Gy (range: 61.6-72.0). Indeed, in patients with mpMRI-detected