Prophylactic versus therapeutic alpha-blockers after permanent prostate brachytherapy

Abstract

Objectives To evaluate the influence of prophylactic versus therapeutic alpha-blockers on urinary morbidity after permanent prostate brachytherapy. Multiple clinical and treatment parameters were evaluated to identify the factors associated with acute urinary morbidity. Methods A total of 234 consecutive patients underwent permanent prostate brachytherapy in one of two prospective randomized studies from October 1999 through February 2001 using either palladium-103 or iodine-125 for clinical Stage T1b-T2b (1997 American Joint Commission on Cancer staging system) prostate cancer at either the Schiffler Cancer Center or Puget Sound Health Care System. The mean and median follow-up was 8.8 ± 4.6 months and 6 months, respectively. In 142 patients, an alpha-blocker was initiated before implantation and continued at least until the International Prostate Symptom Score (IPSS) returned to baseline levels; 92 patients either did not receive an alpha-blocker or received a therapeutic alpha-blocker after implantation because of urinary obstructive symptoms. The clinical and treatment parameters evaluated for urinary morbidity included prophylactic versus therapeutic alpha-blockers, age, preimplant IPSS, ultrasound volume, use of neoadjuvant hormones, use of supplemental external beam radiotherapy, isotope, urethral dose, and multiple dosimetric quality indicators (minimal dose received by 90% of the prostate gland and percentage of prostate volume receiving 100% or 200% of the prescribed minimal peripheral dose). Catheter dependency and the duration of alpha-blocker dependency were also evaluated. Results In both the prophylactic and the therapeutic cohorts, the IPSS peaked 1 month after implantation. Patients receiving a prophylactic alpha-blocker returned to baseline at a mean of 4 months and a median of 3 months postoperatively. For those patients not receiving prophylactic alpha-blockers, the IPSS returned to the antecedent value at a mean and median of 10 months and 6 months, respectively. Of the 125 patients receiving prophylactic alpha-blockers, 102 (81.2%) remained medication dependent at the conclusion of the study, and 140 (78.2%) of 179 patients receiving alpha-blockers other than for hypertensive purposes did so. The incidence of prolonged urinary catheter dependency (greater than 3 days) and the need for postimplant transuretheral incision of the prostate/transurethral resection of the prostate were not affected by alpha-blocker use. Cox regression analysis revealed that only the prophylactic use of alpha-blockers and the difference between the preimplant IPSS and the 1-month IPSS were predictive of the time to return to the referent zone. Conclusions Prophylactic use of alpha-blockers results in significantly less urinary morbidity than either the absence or therapeutic use of alpha-blockers. In patients receiving prophylactic alpha-blockers, the IPSS normalized significantly faster but had no impact on urinary retention or the ultimate need for postimplant surgical intervention.