Adjuvant radiation therapy does not cause urinary incontinence after radical prostatectomy: results of a prospective randomized study.

PURPOSE We analyzed the potential influence of adjuvant radiotherapy on urinary continence after radical prostatectomy. MATERIALS AND METHODS A total of 100 patients with N0M0 prostate cancer randomized in a prospective study on postoperative radiotherapy for locally advanced disease (positive surgical margin, capsular perforation and/or seminal vesicle infiltration) were studied. Objective pad weighing tests corroborated by direct personal interviews were used to evaluate urinary continence at regular postoperative intervals. RESULTS Of the patients 48 received 60 Gy. external radiotherapy with 18 MV photon beams between 12 and 16 weeks postoperatively, and 52 were followed expectantly. Risk factors were similar in both groups. With a mean followup of 24 months, no difference in complete urinary continence was observed. Of the irradiated group 77% and of the surveillance group 83% were totally dry. The fate of the bladder neck had no significant influence on final continence status, although there was a trend for faster recovery when the bladder neck was preserved. CONCLUSIONS In this prospective randomized study 60 Gy. external radiation therapy administered between 3 and 4 months after radical prostatectomy for pathologically locally advanced prostate cancer had no significant influence on urinary continence.