ESTRO 2025 - Abstract Book

S1953

Clinical - Urology

ESTRO 2025

Conclusion: AD ASTRA study protocol allows systemic and local treatment intensification for men with high-risk PCa. We observed high adherence and no new safety signals were identified for the combination of apalutamide with ADT and prostate and pelvic SBRT.

Keywords: prostate and pelvic SBRT, acute toxicity

References: 1. Bolla M et al. External irradiation with or without long-term androgen suppression for prostate cancer with high metastatic risk: 10-year results of an EORTC randomised study. Lancet Oncol.2010;11:1066-1073. 2. Attard G et al. Systemic therapy in advancing or metastatic prostate cancer: evaluation of drug efficacy (STAMPEDE) investigators. Abiraterone acetate and prednisolone with or without enzalutamide for high risk non-metastatic prostate cancer. Lancet.2022;399:447-460. 3. Kissel M et al. Dose escalation in prostate cancer: Results of randomized trials. Cancer Radiother. 2022;26:899-904. 4. Prostate-only versus whole-pelvic radiation therapy in high-risk and very high-risk prostate cancer (POP-RT). J Clin Oncol.2021;39:1234-1252.

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Digital Poster Pushing the boundaries of SBRT in irradiated territories for nodal oligorecurrent prostate cancer: outcomes of the CYGNUS retrospective study Ewen Anger 1 , Stéphane Supiot 2 , Pierre Blanchard 3 , Mario Terlizzi 3 , Quentin Josset 4 , David Pasquier 5 , Loïg Vaugier 2,6 , François-Georges Riet 7 , Yoann Pointreau 8 , Geneviève Loos 9 , Etienne Martin 10 , Paul Sargos 11 , Marie Guerni 11 , Ulrike Schick 12 , Guillaume Bera 6 , Julien Roman 13 , Igor Latorzeff 14 , Gilles Créhanges 15 , Joël Castelli 1,16 , Anais Barateau 1,16 , Renaud De Crevoisier 1,16 , Jennifer Le Guévelou 1 1 Departement of Radiation Oncology, Centre Eugène Marquis, Rennes, France. 2 Departement of Radiation Oncology, Institut de Cancérologie de l’Ouest, Nantes, France. 3 Departement of Radiation Oncology, Gustave Roussy, Villejuif, France. 4 Departement of Radiation Oncology, Institut de Cancérologie de l’Ouest, Angers, France. 5 Academic Radiation Oncology Departement, Centre Oscar Lambret, Lille, France. 6 Departement of Radiation Oncology, Hôpital du Scorff, Lorient, France. 7 Departement of Radiation Oncology, Institut de Cancérologie Régional Bretillien, Saint Grégoire, France. 8 Departement of Radiation Oncology, Centre Jean Bernard, Le Mans, France. 9 Departement of Radiation Oncology, Centre Jean Perrin, Clermont-Ferrand, France. 10 Departement of Radiation Oncology, Georges Francois Leclerc Cancer Center, Dijon, France. 11 Departement of Radiation Oncology, Institut Bergonié, Bordeaux, France. 12 Departement of Radiation Oncology, University Hospital, Brest, France. 13 Departement of Radiation Oncology, Centre Saint Yves, Vannes, France. 14 Departement of Radiation Oncology, Clinique Pasteur, Toulouse, France. 15 Service d'oncologie radiothérapie, Institut Curie, Paris, France. 16 LTSI, Université de Rennes 1, Rennes, France Purpose/Objective: The CYGNUS study aims to assess both toxicity and efficacy of stereotactic body radiotherapy (SBRT) performed as salvage approach for hormone-sensitive pelvic nodal metachronous oligorecurrent (PNMOR) prostate cancer (PCa), in previously irradiated territory. Material/Methods: Inclusion criteria were histologically history of proven PCa, locally treated with a radical intent presenting a biochemical relapse (BCR) as defined by the European Association of Urology guidelines. All patients had a radiological suspicion of PNMOR, defined as a recurrence occurring in pelvic nodal areas (up to the aortic