Risk of urinary incontinence following post-brachytherapy transurethral resection of the prostate and correlation with clinical and treatment parameters.

PURPOSE: We assess the risk of urinary incontinence after transurethral prostate resection in patients previously treated with prostate brachytherapy.
MATERIALS AND METHODS: A total of 2,495 patients underwent brachytherapy with or without external beam radiation therapy for the diagnosis of prostate cancer between June 1990 and December 2009. Patients who underwent transurethral prostate resection before implantation were excluded from study. Overall 79 patients (3.3%) underwent channel transurethral resection of the prostate due to urinary retention or refractory obstructive urinary symptoms. Correlation analyses were performed using the chi-square (Pearson) test. Estimates for time to urinary incontinence were determined using the Kaplan-Meier method with comparisons using logistic regression and Cox proportional hazard rates.
RESULTS: Median followup after implantation was 7.2 years. Median time to first transurethral prostate resection after implantation was 14.8 months. Of the 79 patients who underwent transurethral prostate resection after implantation 20 (25.3%) had urinary incontinence compared with 3.1% of those who underwent implantation only (OR 10.4, 95% CI 6-18, p<0.001). Of the 15 patients who required more than 1 transurethral prostate resection, urinary incontinence developed in 8 (53%) compared with 19% of patients who underwent only 1 resection (OR 4.9, 95% CI 1.5-16, p=0.006). Exclusion of patients who underwent multiple transurethral prostate resections still demonstrated significant differences (18.8% vs 3.1%, OR 7.1, 95% CI 3.6-13.9, p<0.001). Median time from last transurethral prostate resection to urinary incontinence was 24 months. On linear regression analysis, hormone use and transurethral prostate resection after implantation were associated with urinary incontinence (p<0.05). There was no correlation between the timing of transurethral prostate resection after implantation and the risk of incontinence.
CONCLUSIONS: Urinary incontinence developed in 25.3% of patients who underwent transurethral prostate resection after prostate brachytherapy. The risk of urinary incontinence correlates with the number of transurethral prostate resections. Patients should be counseled thoroughly before undergoing transurethral prostate resection after implantation.