Preimplant predictive factors of urinary retention after iodine 125 prostate Brachytherapy

OBJECTIVES To assess the rate and predictive factors of urinary retention after iodine 125 brachytherapy for localized prostate cancer. METHODS Between 1998 and 2006, 655 patients with localized prostate cancer (T1-2, Gleason score 7 or less) were treated with brachytherapy at our institution. 42% received neoadjuvant hormono-therapy for prostate downsizind or when brachytherapy was combined with external beam radiation (10%). They underwent real-time interactive implantation (79%) or a preplanned technique (21%). Clinical, treatment-related and dosimetric factors were evaluated for catheterization requirment because of urinary retention. All patients received alpha(1)-blockers before and throughout at least 30 days posttreatment. RESULT Twenty-one (3.2%) patients required catheterization because of urinary retention. Median time to retention onset was 1 day postimplantation. Univariate and multivariate analyses demonstrated that preimplant ultrasound (US)-based prostate volume and preimplant international prostate sympton scores (IPSS) were significant independent predictive factors for urinary retention (odd ratio [OR] = 6.8 and 3.1, 95% Cl = 2.3-11.4 and 0.2-5.9, P = 0.02 and P = 0.03, respectively). Eight catheterized patients were successfully relieved from their catheter by nonsurgical means and 13 underwent minimal (channeling) transurethral resection of the prostate (TUR-P) not earlier than 6 months postimplant. Mean volume of resected prostate tissue was 9.9 mL (range 4.5-15). The perioperative and postoperative courses were unevenful. There was no TUR-P-related incontinence. CONCLUSIONS Catherization for acute urinary retention after brachytherapy is an uncommon event. Our data suggest that preimplant US-based prostate volume IPSS are the stonger predictors for catheterization. Catheterized patients who are refractory to medical therapy can safely undergo a minimal TUR-P.