Global update on defining and treating high‐risk localized prostate cancer with leuprorelin: a Japanese perspective – the effect of primary androgen deprivation therapy on stage C prostate cancer

Abstract

Stage C prostate cancer, where the tumour has extended beyond the capsule of the prostate, is typically a high-risk disease. According to the National Cancer Institute Physician Data Query the treatments of choice for stage C disease comprise external beam radiation therapy (with or without the addition of adjuvant hormone therapy), androgen deprivation by either surgery or hormone therapy, radical prostatectomy, or careful observation. From 2001, the Japanese Urological Association initiated computer-based registration of all patients with prostate cancer in Japan. Data show that overall, 57% of all patients and 46% of those with T1c to T3 disease had primary androgen deprivation therapy (PADT). Similarly, the Japanese Prostate Cancer Group undertook a large-scale epidemiological surveillance study in Japan and found that the most commonly used hormone therapy is PADT, regardless of disease stage. To date, two randomized, controlled trials of the effect of PADT on stage C prostate cancer in elderly (> or =75 years old) patients have been undertaken in Japan. The results showed that patients with locally advanced prostate cancer treated with PADT are likely to have a life-expectancy similar to that of the normal population. In one study, combined androgen blockade (CAB) with leuprorelin plus chlormadinone appeared to prolong time to disease progression when compared with leuprorelin monotherapy, but there was no difference in survival between these treatment groups. In a second study CAB with an luteinizing hormone-releasing hormone (LHRH) agonist plus bicalutamide was found to prolong time to progression when compared with LHRH agonist monotherapy, but survival results for these regimens are still awaited.