Early Postoperative Radiotherapy is Associated with Worse Functional Outcomes in Patients with Prostate Cancer

Purpose The effect of time between radical prostatectomy and radiation therapy on postoperative functional outcomes is still unclear in patients with surgically managed prostate cancer. We hypothesized that a shorter time between radical prostatectomy and radiotherapy might be associated with worse functional recovery rates after radical prostatectomy. Materials and Methods We retrospectively evaluated 2,190 patients treated with radical prostatectomy and stratified according to radiotherapy schedule (adjuvant radiotherapy, salvage radiotherapy, no radiotherapy). We examined recovery rates for erectile function and urinary function according to adjuvant radiotherapy, salvage radiotherapy and no radiotherapy, and according to time from surgery to radiotherapy. Cox regression analyses were used to evaluate the impact of these predictors on functional outcomes. Results Median followup was 48 months. The 3-year erectile function recovery rates were 35.0%, 29.0% and 11.6% in patients who received no radiotherapy, salvage radiotherapy and adjuvant radiotherapy, respectively (p <0.001), and differed significantly according to time to radiotherapy (11.7% vs 34.7% for less than 1 year vs 1 year or more, respectively, p <0.001). The 3-year urinary continence recovery rates were 70.7%, 59.0% and 42.2% in patients who received no radiotherapy, salvage radiotherapy and adjuvant radiotherapy, respectively (p <0.001), and differed according to time to radiotherapy (43.5% vs 62.7% for less than 1 year vs 1 year or more, respectively, p <0.001). Cox regression analyses confirmed the negative impact of early radiotherapy on recovery rates for erectile function and urinary continence. Conclusions Time from radical prostatectomy to radiotherapy has an important role in the recovery of erectile function and urinary continence. Delayed radiotherapy is preferred to improve functional outcomes after surgery.