Clinical Drug Experience Knowledgebase

Randomized, Open-Labeled Study of Prophylactic Vs. Therapeutic Use of Uroxatrol to Determine Improvements in Urinary Morbidity Following Men Undergoing Prostate Brachytherapy

Prostate brachytherapy is an increasingly popular method of treating clinically localized prostate cancer. The major morbidity of this procedure is obstructive and irritative voiding symptoms. The risk of urinary retention in published series is 10-15%. Voiding symptoms persist up to 1 year following this procedure.

The primary experience in treating obstructive and irritative voiding symptoms is in men with benign prostatic hyperplasia (BPH). In patients with moderate to severe voiding symptomatology, based in the American Urological Association (AUA) Symptom Score Index, medical treatment with alpha antagonists has become commonplace. The use of alpha antagonists is based upon the reduction of smooth muscle tone in both the prostate gland and urinary bladder neck by inhibition of alpha1 adrenoceptor, resulting in relaxation of bladder outlet obstruction and increased urinary flow.

Alfuzosin hydrochloride was approved by the FDA for treatment of the signs and symptoms of BPH in 2003. Alfuzosin differs from other  1-adrenergic receptor blockers by the absences of a piperidine moiety and the presence of a diaminopropyl spacer, which confers alfuzosin with specific biochemical properties. Affinity studies on human-cloned  1 receptor subtypes show that alfuzosin, like terazosin and doxazosin, is devoid of significant receptor subtype selectivity. In isolated human tissues, however, alfuzosin displays the highest selectivity ratio for the prostate over the vascular tissue (ratio, 544) compared with tamsulosin (90), doxazosin (51), and terazosin (19).

Prostate cancer is the most common malignancy in men. One of the most common treatments of prostate cancer is prostate brachytherapy, or radioactive seed implantation. All patients are affected by obstructive and irritative voiding symptoms to various degrees following this procedure due to edema and inflammation induced by trauma and radiation. Many physicians routinely treat obstructive and irritative voiding symptoms following prostate brachytherapy with alpha-blockers. Patients presenting with clinically localized prostate cancer may elect permanent prostate brachytherapy as definitive therapy. The efficacy of such therapy matches that of radical prostatectomy or external beam radiation. Many patients select brachytherapy since it is a single treatment session that is considered minor surgery. Most patients are discharged the same day and they may resume their normal physical activities without restriction almost immediately.

However, the trauma of the needle sticks through the perineum coupled with the effects of the radiation can cause a prostatitis with symptoms similar to irritable bladder or benign prostatic hypertrophy. These symptoms can have considerable impact on the quality of life of the patient and many are medicated with alpha-blockers.

Several studies have attempted to define how best to predict for and treat these symptoms. However, the incidence and severity of these symptoms is difficult to predict. The prophylactic use of alpha-blockers may better control these symptoms in some men undergoing prostate brachytherapy. The aim of this study is to compare outcomes of urinary morbidity following prostate brachytherapy between patients treated with alfuzosin prior to implantation and patients treated following implantation.