A retrospective study of the treatment of locally advanced prostate cancer by six institutions in eastern and north-eastern Japan

OBJECTIVE To investigate patients with locally advanced prostate cancer treated at six academic institutions in eastern and north-eastern Japan from 1988 to 2000, to facilitate the establishment of Japanese guidelines for the diagnosis and treatment of locally advanced prostate cancer. PATIENTS AND METHODS The study included 391 eligible patients with locally advanced prostate cancer who were treated by radical prostatectomy (RP), radiotherapy and/or primary hormone therapy. Disease-specific survival rates for these patients were assessed in relation to their clinicopathological characteristics and the types of treatment they received. The Mann-Whitney U-test, Kruskal-Wallis, chi-square and log-rank test were used for statistical analysis, as appropriate. RESULTS In all, 128 patient with lower prostate-specific antigen levels (P = 0.023) and/or better performance status (P = 0.001) had RP. Neoadjuvant hormone therapy before RP was the treatment in 68 (53%) of these 128 patients; 66 (52%) received immediate adjuvant hormone therapy. Of 87 patients treated with radiotherapy, 75 (86%) had external beam radiotherapy (EBRT) as the primary treatment with no brachytherapy, and 12 (14%) had brachytherapy as the primary method. Neoadjuvant hormone therapy was given to 56 of the 87 patients (64%); 48 (55%) received immediate adjuvant hormone therapy. Of the 176 patients treated with primary hormone therapy alone, combined androgen blockade and surgical or medical castration was the treatment in 76 (43%) and 85 (48%), respectively. Disease-specific survival rates at 5 years for patients treated with RP, EBRT and primary hormone therapy were 90%, 98%, and 89%, respectively. CONCLUSION The treatments provided by the participating institutions did not differ significantly from those set out in European and American guidelines, and short-term disease-specific survival rates for each treatment did not differ significantly from those of historical controls. Further investigation may facilitate the establishment of Japanese guidelines for the diagnosis and treatment of locally advanced prostate cancer.