The pathophysiology of lower urinary tract symptoms after brachytherapy for prostate cancer

Abstract

To determine the spectrum of pathophysiology underlying the lower urinary tract symptoms (LUTS) persisting for > or = 6 months after brachytherapy for localized prostate cancer. A database of men from two practice settings was searched for men who developed LUTS persisting for > or = 6 months after completing brachytherapy for localized prostate cancer. Patients were evaluated with a structured history and physical examination, International Prostate Symptom Score (IPSS), 24-h voiding diary, noninvasive free-flow uroflowmetry, postvoid residual urine volume (PVR), cystoscopy and a video-urodynamic study. Specific data collected included symptoms, elapsed time since brachytherapy, Gleason score, IPSS, total number of voids/24 h, maximum voided volume, cystoscopic findings, and urodynamics findings (PVR, maximum urinary flow rate, Schaefer obstruction grade, Watts factor, incidence of detrusor overactivity (DO) urethral obstruction and low bladder compliance). These data were compared with those from a previous study of men with LUTS who did not have prostate cancer. The study included 47 men (aged 54-88 years); the median (range) interval between brachytherapy and evaluation was 1.5 (0.5-13) years. Thirty-seven men complained of overactive bladder symptoms (79%), and 31 of incontinence (71%), 21 of obstructive symptoms (44%), and persistent dysuria in 12 (26%). Comparison of urodynamic findings in men with unselected causes of LUTS vs LUTS due to brachytherapy revealed the following comparisons: DO in 252 of 541 (47%) unselected vs 28 of 33 (85%) brachytherapy, (P < 0.001); and urethral obstruction in 374 of 541 (69%) unselected vs 24 of 33 (73%) brachytherapy (P = 0.85). The pathophysiology and severity of persistent LUTS in men after brachytherapy differs from that of men with LUTS in the general population. Men after brachytherapy have a much higher incidence of DO, prostatic and urethral strictures and prostatic urethral stones.