While SBRT to the prostate has become a valuable option as a radical treatment, limited data support its use in the postoperative setting. Here, we report the updated results of the multicentric Post-Prostatectomy Ablative Radiation Therapy (POPART) trial, investigating possible predictors of toxicities and patient-reported outcomes.
Patients with PSA levels between 0.1-2.0 ng/mL after radical prostatectomy received Linac-based SBRT to the prostate bed in five fractions every other day for a total dose of 32.5 Gy (EQD21.5 = 74.3 Gy). Late toxicity was assessed using CTCAE v.5 scale, while EPIC-CP, ICIQ-SF, IIEF 5 questionnaires and PSA levels measured quality of life and biochemical control. Pre- and post-treatment scores were compared using a paired t-test, with MID established at > 0.5 pooled SD from the baseline. A logistic regression analysis was performed to evaluate potential associations between specific patient/tumor/treatment factors and outcome deterioration.
From April 2021 to April 2023 a total of 50 pts were enrolled and treated. Median follow-up was 12.2 (3-27) months. No late ≥ G2 GI or GU toxicity was registered. Late G1 urinary and rectal toxicities occurred in 46 % and 4 % of patients, respectively. Among 47 patients completing all EPIC-CP domains, four (9 %) showed worsened QoL, and eleven (26 %) developed erectile dysfunction correlating with PTV D2% (P = 0.032). At Multivariate analysis bladder wall D10cc independently correlated with late G1 GU toxicity (P = 0.034). Median post-treatment PSA nadir was 0.04 ng/mL (0.00 - 0.84). At the last follow-up, six patients presented with biochemical failure, including two nodal relapses.
Our findings show that post-prostatectomy SBRT did not result in increased toxicity nor a significant decline in QoL measures, thus showing that it can be safely extended to the postoperative setting. Long-term follow-up and randomized comparisons with different RT schedules are needed to validate this approach.
Clinical and translational radiation oncology. 2023 Nov 25*** epublish ***
Federica Ferrario, Ciro Franzese, Valeria Faccenda, Suela Vukcaj, Maria Belmonte, Raffaella Lucchini, Davide Baldaccini, Marco Badalamenti, Stefano Andreoli, Denis Panizza, Alessandro Magli, Marta Scorsetti, Stefano Arcangeli
School of Medicine and Surgery, University of Milan Bicocca, 20126 Milan, Italy., Department of Biomedical Sciences, Humanitas University, 20090 Pieve Emanuele (MI), Italy., Department of Medical Physics, Fondazione IRCCS San Gerardo dei Tintori, 20900 Monza, Italy., Department of Radiation Oncology, ASST Papa Giovanni XXIII, 24127 Bergamo, Italy., Radiotherapy and Radiosurgery Department, IRCCS Humanitas Research Hospital, 20089 Rozzano (MI), Italy., Department of Medical Physics, ASST Papa Giovanni XXIII, 24127 Bergamo, Italy., Department of Radiation Oncology, AULSS 1 Dolomiti, 32100 Belluno, Italy.