ESTRO 2024 - Abstract Book

S2437

Clinical - Urology

ESTRO 2024

Whole vs. hemi pelvis RT in patients with PSMA-positive nodal recurrence - a retrospective analysis

Christian Trapp 1 , Daniel M. Aebersold 2 , Claus Belka 1,3 , Jozefina Casuscelli 4 , Francesco Ceci 5,6 , Louise Emmett 7,8 , Stefano Fanti 9 , Andrea Farolfi 9 , Anca-Ligia Grosu 10,11 , Matthias Guckenberger 12 , Christoph Henkenberens 13 , George Hruby 14 , Stefan A. Koerber 15,16 , Stephanie Kroeze 12 , Jan C. Peeken 17,3 , Paul Rogowski 1 , Sophia Scharl 18 , Mohamed Shelan 2 , Simon K.B. Spohn 10,11,19 , Iosif Strouthos 20 , Lena Unterrainer 21 , Marco Vogel 17,3 , Thomas Wiegel 18 , Constantinos Zamboglou 20,10,11 , Nina-Sophie Schmidt-Hegemann 1 1 LMU Munich, University Hospital, Department of Radiation Oncology, Munich, Germany. 2 University of Bern, Inselspital, Department of Radiation Oncology, Bern, Switzerland. 3 Deutsches Konsortium für Translationale Krebsforschung (DKTK), Partner Site Munich, Munich, Germany. 4 LMU Munich, University Hospital, Department of Urology, Munich, Germany. 5 IEO European Institute of Oncology IRCCS, Division of Nuclear Medicine, Milan, Italy. 6 University of Milan, Department of Oncology and Hemato-Oncology, Milan, Italy. 7 St. Vincent's Hospital, Department of Theranostics and Nuclear Medicine, Sydney, Australia. 8 University of New South Wales, St. Vincent's Clinical School, Sydney, Australia. 9 IRCCS Azienda Ospedaliero-Universitaria di Bologna, Division of Nuclear Medicine, Bologna, Italy. 10 University of Freiburg, Medical Center, Department of Radiation Oncology, Freiburg, Germany. 11 Deutsches Konsortium für Translationale Krebsforschung (DKTK), Partner Site Freiburg, Freiburg, Germany. 12 University of Zurich, University Hospital, Department of Radiation Oncology, Zurich, Switzerland. 13 Medical School Hannover, Department of Radiotherapy and Special Oncology, Hannover, Germany. 14 University of Sydney, Royal North Shore Hospital, Department of Radiation Oncology, Sydney, Australia. 15 Barmherzige Brüder Hospital Regensburg, Department of Radiation Oncology, Regensburg, Germany. 16 Heidelberg University Hospital, Department of Radiation Oncology, Heidelberg, Germany. 17 Technical University of Munich (TUM), Klinikum rechts der Isar, Department of Radiation Oncology, Munich, Germany. 18 University of Ulm, Department of Radiation Oncology, Ulm, Germany. 19 University of Freiburg, Medical Faculty, Berta-Ottenstein-Programm, Freiburg, Germany. 20 European University Cyprus, German Oncology Center, Department of Radiation Oncology, Nicosia, Cyprus. 21 LMU Munich, University Hospital, Department of Nuclear Medicine, Munich, Germany Radiotherapy (RT) is a mainstay of therapy for lymph node (LN) recurrent prostate cancer (PC) after prostatectomy. While there is growing evidence in this situation for stereotactic body RT (SBRT) and RT of the bilateral pelvic lymphatic pathways (whole pelvis RT, WPRT), there is almost no data on RT of unilateral pelvic lymphatic pathways (hemi pelvis RT, HPRT) on the side of LN. Nevertheless, in clinical practice HPRT is sometimes used with the intention to reduce the treatment volume and side effects compared with WPRT. In general, WPRT and HPRT are combined with simultaneous integrated boosts to LN. PSMA-PET/CT is currently the best imaging modality for staging in this clinical situation due to its high sensitivity and specificity. The aim of this retrospective multi institutional analysis was to compare outcomes of both RT strategies in patients undergoing PSMA-PET/CT based RT of the pelvic lymphatic pathways. Purpose/Objective:

Material/Methods:

A propensity score matching based on ISUP score, PSA before PSMA-PET/CT, age and ADT during RT was performed in a multi-institutional retrospective dataset of 273 patients with nodal recurrent PC treated with PSMA-PET/CT guided pelvic RT (214 WPRT, 59 HPRT). In total, 102 patients (51 patients in each group) were included in the final