Vienna, Austria

ESTRO 2023

Session Item

Urology
6018
Poster (Digital)
Clinical
Stereotactic re-RT for local recurrence of PCa after primary surgery and RT: a retrospective study.
Mattia Zaffaroni, Italy
PO-1498

Abstract

Stereotactic re-RT for local recurrence of PCa after primary surgery and RT: a retrospective study.
Authors:

Chiara Lorubbio1,2, Ilaria Repetti1,2, Giulia Marvaso1,2, Giulia Corrao1,2, Matteo Pepa1, Mattia Zaffaroni1, Maria Giulia Vincini1, Dario Zerini1, Cristiana Fodor1, Gennaro Musi2,3, Giuseppe Petralia2,4, Ottavio De Cobelli2,3, Federica Cattani5, Roberto Orecchia6, Barbara Alicja Jereczek-Fossa1,2

1IEO, European Institute of Oncology, IRCCS, Division of Radiation Oncology, Milan, Italy; 2University of Milan, Department of Oncology and Hemato-Oncology, Milan, Italy; 3IEO, European Institute of Oncology, IRCCS, Division of Urology, Milan, Italy; 4IEO, European Institute of Oncology, IRCCS, Precision Imaging and Research Unit, Department of Medical Imaging and Radiation Sciences, Milan, Italy; 5IEO, European Institute of Oncology, IRCCS, Unit of Medical Physics, Milan, Italy; 6IEO, European Institute of Oncology, IRCCS, Scientific Directorate, Milan, Italy

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Purpose or Objective

Re-irradiation by stereotactic body radiotherapy (SBRT) represents a valid option for treating locally recurrent prostate cancer (PCa). The aim of this retrospective study was to determine the efficacy and safety of such treatment.

Material and Methods

The study included patients who underwent salvage radiotherapy for isolated PCa local recurrence after primary surgery and previous salvage/adjuvant radiotherapy or brachytherapy at our Institution between 2010 and 2021. Patients who received hormone therapy and those who underwent more than one local re-irradiation were also included. Local relapse in the prostate bed was assessed by MRI and/or choline or PSMA-PET. Histological confirmation was not mandatory. Salvage SBRT re-irradiation was delivered with image-guided radiation therapy (IGRT) using the BrainLab VERO System.

Results

Forty-five patients met the inclusion criteria and were included in the study. Patients and treatment characteristics are listed in Table 1. Most lesions (29 out of 45, 64.4%) were peri-anastomotic. PET was available for 25 (55.5%) and MRI for 39 (86.7%) patients. Five patients (11.1%) received more than one SBRT treatments for prostate bed recurrence, with one of them (2.2%) receiving three re-irradiations. Among the 38 patients with updated follow-up data, 8 (21.1%) resulted free from disease at last contact. Progression of disease (PD) was observed in 30 out of 38 patients (78.9%) with 16 clinical and 14 biochemical progressions. Median time to clinical and biochemical progression were, respectively, 15.5 (IQR: 10.7 – 21.9) and 14.0 months (IQR: 10.7 – 41.9). Of them, only one patient experienced polyprogression. Regarding acute toxicity outcomes, no genitourinary (GU) events higher than grade (G) 1 and no gastrointestinal (GI) events higher than G2 occurred.
During follow-up, no patients but three experienced GU/GI events higher than 2. One patient experienced G3 GU maximum toxicity with implantation of an artificial urinary sphincter after worsening of urinary incontinence, which however decreased to G0 at last contact. Two patients experienced late G4 GU toxicity: one of them had acute urinary retention with bladder catheter positioning – turning into G2 at last follow-up; the other one underwent internal urethrotomy. None of the patients experienced late GI toxicity.


Conclusion

Salvage stereotactic re-irradiation treatment for locally recurrent PCa seems to be a safe and promising strategy to control bed recurrence. Further studies and longer follow-up are warranted to confirm these preliminary findings.