A prospective phase II study of prostate-specific antigen-guided salvage radiotherapy and 68Ga-PSMA-PET for biochemical relapse after radical prostatectomy – The PROPER 1 trial

•PSA response during the first weeks of salvage radiotherapy (SRT) of prostate cancer is highly predictive for tumour control.•PSA responders received conventional local SRT towards the prostate bed while the treatment plan of PSA non-responders was changed after 5 weeks of SRT to also include pelvic lymph nodes/metastases.•High tumour control rate with moderate side effects were observed in both PSA responders and non-responders with this new personalised treatment concept.•It is now further investigated in a prospective phase III trial (NCT04858880).