PH-0659 Metastasis-free survival after salvage radiotherapy in post-operative prostate cancer patients in the PSMA PET/CT era – a bi-institutional, retrospective analysis. (August 2021) - Schmidt-Hegemann, N.; Grosu, A.L.; Ruf, J.; Gratzke, C.; Adebahr, S.; Stief, C.; Bartenstein, P.; Belka, C.; Li, M.; Trapp, C.; Rogowski, P.; Zamboglou, C.