Long‐term effectiveness of luteinizing hormone‐releasing hormone agonist or antiandrogen monotherapy in elderly men with localized prostate cancer (T1‐2) : a retrospective study

Aim: To evaluate the long‐term effectiveness, side effects and compliance rates of two types of drugs (luteinizing hormone‐releasing hormone [LHRH] agonist and antiandrogen) that were used individually to treat patients with localized prostate cancer (T1‐2) at our institution. Methods: Ninety‐seven patients who were diagnosed in the period from April 1997 to January 2000 as having clinically localized prostate cancer (T1‐2) received either LHRH agonist (leuprolide acetate 7.5 mg/month) monotherapy (group 1, n = 62) or antiandrogen monotherapy (group 2, n = 35; 18 received bicalutamide 50 mg q.d., 13 received nilutamide 150 mg t.i.d. and 4 received flutamide 250 mg t.i.d.). The mean age in both groups was 76 years. Results: The mean follow‐up time was (50.8 ± 8.5) months in group 1 and (43.1 ± 2.2) months in group 2. Prostate‐specific antigen (PSA) levels rose in only 1 of the 62 patients (1.6%) in group 1, and in 20 of the 35 patients (57.1%) in group 2. In group 2, 10 of the 20 patients (50%) with increasing PSA levels were treated with LHRH salvage therapy, and eight (80%) responded. Hot flashes (54.8%) and lethargy (41.9%) were the most common side effects in group 1. In contrast, nipple‐tenderness (40%) and light‐dark adaptation (17.1%) were more often seen in group 2. Only 1 of the 62 patients (1.6%) in group 1 switched to another medication because of adverse side effects; whereas 8 of the 35 patients (22.9%) in group 2 did so. Conclusion: Unlike antiandrogen monotherapy, LHRH agonist monotherapy provided long‐term durable control of localized prostate cancer (T1‐2). It can also be an effective treatment option for patients whose disease failed to respond to antiandrogen monotherapy. The limitations of our study are the lack of health outcomes analysis and a small sample size.