Erectile function preservation after salvage radiation therapy for biochemically recurrent prostate cancer after prostatectomy: Five-year results of the SAKK 09/10 randomized phase 3 trial.

To evaluate effects of dose intensified salvage radiotherapy (sRT) on erectile function in biochemically recurrent prostate cancer (PC) after radical prostatectomy (RP).

Eligible patients had evidence of biochemical failure after RP and a PSA at randomization of ≤ 2 ng/ml. Erectile dysfunction (ED) was investigated as secondary endpoint within the multicentre randomized trial (February 2011 to April 2014) in patients receiving either 64 Gy or 70 Gy sRT. ED and quality of life (QoL) were assessed using CTCAE v4.0 and the EORTC QoL questionnaires C30 and PR25 at baseline and up to 5 years after sRT.

344 patients were evaluable. After RP 197 (57.3 %) patients had G0-2 ED while G3 ED was recorded in 147 (42.7 %) patients. Subsequently, sexual activity and functioning was impaired. 5 years after sRT, 101 (29.4 %) patients noted G0-2 ED. During follow-up, 44.2 % of patients with baseline G3 ED showed any improvement and 61.4 % of patients with baseline G0-2 ED showed worsening. Shorter time interval between RP and start of sRT (p = 0.007) and older age at randomization (p = 0.005) were significant predictors to more baseline ED and low sexual activity in the long-term. Age (p = 0.010) and RT technique (p = 0.031) had a significant impact on occurrence of long-term ED grade 3 and worse sexual functioning. During follow-up, no differences were found in erectile function, sexual activity, and sexual functioning between the 64 Gy and 70 Gy arm.

ED after RP is a known long-term side effect with significant impact on patients' QoL. ED was further affected by sRT, but dose intensification of sRT showed no significant impact on erectile function recovery or prevalence of de novo ED after sRT. Age, tumor stage, prostatectomy and RT-techniques, nerve-sparing and observation time were associated with long-term erectile function outcome.ClinicalTrials.gov. Identifier: NCT01272050.

Clinical and translational radiation oncology. 2024 Apr 25*** epublish ***

Daniel R Zwahlen, Christina Schröder, Lisa Holer, Jürg Bernhard, Tobias Hölscher, Winfried Arnold, Bülent Polat, Guido Hildebrandt, Arndt-Christian Müller, Paul Martin Putora, Alexandros Papachristofilou, Corinne Schär, Stefanie Hayoz, Marcin Sumila, Kathrin Zaugg, Matthias Guckenberger, Piet Ost, Davide Giovanni Bosetti, Christiane Reuter, Silvia Gomez, Kaouthar Khanfir, Marcus Beck, George N Thalmann, Daniel M Aebersold, Pirus Ghadjar

Kantonsspital Winterthur, Winterthur, Switzerland., Swiss Group for Clinical Cancer Research Competence Center, Bern, Switzerland., Inselspital, Bern University Hospital, and Bern University, Bern, Switzerland., University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany., Kantonsspital Luzern, Lucerne, Switzerland., University Hospital Würzburg, Würzburg, Germany., University Hospital Rostock, Rostock, Germany., University Hospital Tübingen, Tübingen, Germany., Kantonsspital Sankt Gallen, Sankt Gallen, Switzerland., University Hospital Basel, Basel, Switzerland., Hirslanden Hospital Group, Zurich, Switzerland., Stadtspital Triemli, Zurich, Switzerland., University Hospital Zurich, Zurich, Switzerland., Ghent University Hospital, Ghent, Belgium., Istituto Oncologico della Svizzera Italiana, Bellinzona, Switzerland., Kantonsspital Münsterlingen, Münsterlingen, Switzerland., Kantonsspital Aarau, Aarau, Switzerland., Hôpital du Valais, Sion, Switzerland., Charité - Universitätsmedizin Berlin, Germany.