Salvage conformal radiotherapy for biochemical recurrent prostate cancer after radical prostatectomy.

OBJECTIVE Assess the results of salvage conformal radiotherapy in patients with biochemical failure after radical prostatectomy and identify prognostic factors for biochemical recurrence and toxicity of the treatment. MATERIALS AND METHODS From June 1998 to November 2001, 35 patients were submitted to conformal radiotherapy for PSA > or = 0.2 ng/mL in progression after radical prostatectomy and were retrospectively analyzed. The mean dose of radiation in prostatic bed was of 77.4 Gy (68-81). Variables related to the treatment and to tumor were assessed to identify prognostic factors for biochemical recurrence after salvage radiotherapy. RESULTS The median follow-up was of 55 months (17-83). The actuarial survival rates free of biochemical recurrence and free of metastasis at a distance of 5 years were 79.7% e 84.7%, respectively. The actuarial global survival rate in 5 years was 96.1%. The actuarial survival rate free of biochemical recurrence in 5 years was 83.3% with PSA pre-radiotherapy < or = 1, 100% when > 1 and < or = 2, and 57.1% when > 2 (p = 0.023). Dose > 70 Gy in 30% of the bladder volume implied in more acute urinary toxicity (p = 0.035). The mean time for the development of late urinary toxicity was 21 months (12-51). Dose > 55 Gy in 50%bladder volume implied in more late urinary toxicity (p = 0.018). A patient presented late rectal toxicity of 2nd grade. CONCLUSIONS Conformal radiotherapy showed to be effective for the control of biochemical recurrence after radical prostatectomy. Patients with pre-therapy PSA < or = 2 ng/mL have more biochemical control.