Impact of a radical prostatectomy on the urodynamic results of prostate cancer patients treated with intensity modulated radiation therapy.

ABSTRACT

INTRODUCTION AND OBJECTIVES: To evaluate the effect of radical prostatectomy and age on urodynamics before and after intensity-modulated radiation therapy administered to prostate cancer patients. MATERIALS AND METHODS: The sample consisted of 40 prostate cancer patients, 22 of whom had undergone a radical prostatectomy. Urodynamic parameters before and after an average of 4.2 months of radiotherapy were measured and compared. External radiotherapy was administered via Volumetric Modulated Arc Therapy (VMAT), Intensity Modulated Radiation Therapy (IMRT) techniques. RESULTS: Uroflowmetry presented no significant parameters. In the case of Cystomanometry, the data did not show an increase in secondary stress urinary incontinence, although there is 7 percent increase in urge urinary incontinence. There were statistically significant changes in reduced bladder capacity with a strong desire to void, with an urge to void and also in the detrusor pressure with a normal desire to void. Furthermore, pressure/flow analysis revealed a statistically significant reduction of residual urine volume. CONCLUSIONS: The effect of prostatectomy and age varies according to the evolution of urodynamics. There was a significant reduction in terms of residual urine volume and detrusor pressure with a normal desire to void in patients without a prostatectomy and in those under 75 years old. In addition to an increase in urge incontinence, there was also a significant worsening of the bladder filling urodynamics and a decrease in the cystomanometric bladder capacity with a strong desire and an urge to void. None of these were modified by age or prostatectomy.