Use of 5-alpha-reductase inhibitors as alternatives to luteinizing-hormone releasing hormone (LHRH) analogs or anti-androgens for prostate downsizing before brachytherapy.

Prostate hypertrophy, median lobe hypertrophy, and pubic arch interference (PAI) are relative contraindications to brachytherapy because of potential morbidity and technical considerations. GnRH analogs or non-steroidal anti-androgens are currently utilized to achieve prostatic downsizing prior to brachytherapy. However, such agents have been associated with effects on body habitus, metabolism, and quality of life. In contrast, 5-alpha reductase inhibitors (5-ARI) are far less frequently associated with these morbidities.Patients with large gland size, median lobe hypertrophy, or PAI were offered 5-ARI therapy. Repeat transrectal ultrasound was performed at 3 or 4 months, followed by brachytherapy if resolution was achieved. If downsizing was inadequate, patients were offered continuation of 5-ARI for additional 3 months, gonadotropin-releasing hormone analog (GnRH) agonist or antiandrogen therapy, or other curative treatment.Of 59 patients with follow-up available, 42 (71%) were deemed to have adequate downsizing; 37 (63%) after 3 to 4 months of 5-ARI and 5 (8%) after 7 to 8 months. Seventeen patients (29%) received other treatments because of inadequate effect. Median volume reduction was 20%. Of 41 patients undergoing brachytherapy, 4 (9.7%) required temporary catheterization because of obstruction. Median follow-up after implantation was 25 months (range, 1-64). Median time for return to International Prostate Symptom Score ≤5 of baseline score was 7 months (interquartile ratio, 6-13). All but 1 patient who received brachytherapy remain biochemically controlled.5-ARI monotherapy is an alternative for downsizing in patients with hypertrophy or PAI, with more than 70% achieving adequate downsizing without use of GnRH analogs or antiandrogens. Patients who received brachytherapy experienced typical rates of postimplant urinary morbidity.