Long-Term Outcomes After High-Dose Postprostatectomy Salvage Radiation Treatment

Purpose To review the impact of high–dose radiotherapy (RT) in the postprostatectomy salvage setting on long-term biochemical control and distant metastases–free survival, and to identify clinical and pathologic predictors of outcomes. Methods and Materials During 1988–2007, 285 consecutive patients were treated with salvage RT (SRT) after radical prostatectomy. All patients were treated with either three-dimensional conformal RT or intensity-modulated RT. Two hundred seventy patients (95%) were treated to a dose ≥66 Gy, of whom 205 (72%) received doses ≥70 Gy. Eighty-seven patients (31%) received androgen-deprivation therapy as a component of their salvage treatment. All clinical and pathologic records were reviewed to identify treatment risk factors and response. Results The median follow-up time after SRT was 60 months. Seven-year actuarial prostate-specific antigen (PSA) relapse-free survival and distant metastases–free survival were 37% and 77%, respectively. Independent predictors of biochemical recurrence were vascular invasion ( p p 0.4 ng/mL ( p p = 0.03), Gleason score ≥7 ( p = 0.02), and seminal vesicle involvement ( p = 0.05). Salvage RT dose ≥70 Gy was not associated with improvement in biochemical control. A doubling time p p = 0.07). Conclusion Salvage RT provides effective long-term biochemical control and freedom from metastasis in selected patients presenting with detectable PSA after prostatectomy. Androgen-deprivation therapy was associated with improvement in biochemical progression-free survival. Clinical local failures were rare but occurred most commonly in patients with greater burden of disease at time of SRT as reflected by either radiographic imaging or a greater PSA level. Salvage radiation doses ≥70 Gy may ultimately be most beneficial in these patients, but this needs to be further studied.