Biochemical relapse in prostate cancer is defined as rising PSA levels after prostatectomy. The only curative option for these patients is the so-called salvage radiotherapy. To increase the efficacy of this treatment, several studies tested the combination of salvage radiotherapy with androgen deprivation therapy. In 2016 two of these studies have published first results: GETUG-AFU 16 and RTOG 9601. In both studies, additional androgen deprivation increased biochemical relapsefree survival at about 20%. However, there are still several issues not addressed in these studies, so a general recommendation to combine salvage radiotherapy with androgen deprivation in all patients with biochemical relapse cannot be given now. In this review, we present the currently available data, address the open questions, and give a short overview of the next study results awaited.