Recurrent disease following radical prostatectomy will occur in approximately 20% of patients, for whom the therapeutic options include surveillance, salvage radiotherapy, or hormonal therapy. This review will focus on the evidence for salvage radiotherapy. Efficacy results of 30โ50% have been reported from multiple retrospective series, with minimal morbidity. Unfortunately there are no randomized or prospective studies in this area. Results of salvage radiotherapy improve when given earlier, ideally with the serum prostate-specific antigen < 1 ng/mL. Other positive prognosticators are positive margins at radical prostatectomy, longer prostate-specific antigen doubling times, lower radical prostatectomy Gleason scores, and the absence of lymph node metastases. Current standard dosage is 64 Gy or slightly higher, although the optimal dosage has yet to be defined with prospective randomized trials. Salvage radiotherapy can provide a durable response when given early, and patients with recurrent disease should be considered for treatment or enrolment in clinical trials. [ABSTRACT FROM AUTHOR]