Objectives: To compare, in a retrospective analysis, the outcome of salvage external beam radiotherapy (EBRT) for isolated prostate-specific antigen (PSA) elevation or palpable local recurrence after radical prostatectomy (RP).
Methods: We evaluated 102 men who underwent EBRT from 1993 to 1999, 60 for a rising PSA level alone and 42 for palpable local disease after RP. Biochemical disease-free survival and overall survival were calculated. Prognostic factors were evaluated to determine associations with biochemical disease-free survival.
Results: The 5-year rate of biochemical disease-free survival, local control, freedom from distant metastasis, and overall survival for all 102 patients was 38%, 94%, 87%, and 88%, respectively. All palpable disease resolved completely after salvage EBRT. The greatest 5-year rate of biochemical control (69%) was obtained in patients with a pre-EBRT PSA level of 0.5 ng/mL or less. The 5-year overall survival rate was significantly better for those who underwent salvage EBRT for a rising PSA level than for those with palpable recurrence (96% versus 78%, P = 0.02). A low pre-EBRT PSA level and a less than 2-year interval from RP to EBRT were independent predictors of biochemical failure. Five patients (5%) experienced chronic grade 3 or 4 RT-related toxicity.
Conclusions: Salvage EBRT provides excellent local control of recurrent disease after RP. Salvage EBRT before the development of palpable local disease may confer a survival benefit and decrease the risk of metastasis, and durable biochemical control was achieved best in those whose pre-EBRT PSA level was 0.5 ng/mL or less. Early referral and careful patient selection is vital for salvage EBRT to be of optimal benefit.