Corresponding author: Prof. Yasar Beduk, M.D Ankara University, Urology, Ankara, Türkiye e-mail: yasarbeduk@superonline.com Marmara Medical Journal 2007;20(2);75-84 ORIGINAL RESEARCH THE COMPARISON OF THE EFFICACY OF CYPROTERONE ACETATE AND CASTRATION MONOTHERAPIES IN METASTATIC PROSTATE CANCER: A MULTICENTER STUDY OF A TURKISH URO-ONCOLOGY GROUP Yasar Beduk 1 , Nural Bekiroğlu 2 , Atıf Aktaş 3 , Haluk Özen 4 , Tarık Esen 5 , Cavit Can 6 , Levent Türkeri 3 1 Department of Urology,School of Medicine,Ankara University,Ankara,Türkiye 2 Department of Biostatistics, School of Medicine,Marmara University, Istanbul, Türkiye 3 Department of Urology, School of Medicine, Marmara University, İstanbul, Türkiye 4 Department of Urology, School of Medicine, Hacettepe University, Ankara, Türkiye 5 Department of Urology, School of Medicine, İstanbul University, İstanbul, Türkiye 6 Department of Urology, School of Medicine, Osmangazi University, Bursa, Türkiye ABSTRACT Objective: To detect the therapeutic efficacy of CPA and to compare it with surgical or medical castration in advanced prostate cancer Patients and Methods: Patients from 19 Urology Centers with prostate adenocarcinoma of stages T1- 4N+MX or T1-4NXM+ were enrolled. A total of 120 patients were randomized to receive CPA 3X100mg/d(Group 1) versus medical or surgical castration(Group 2).The primary endpoints for this trial were overall and disease-spesific survival.Progression-free survival(PSA progression time) and testosterone decrease rate were assessed as secondary endpoints.Progression-free survival probabilities were calculated by the Kaplan-Meier method and comparison of survival probabilities was performed by the Logrank test. Results: The median PSA values were 42ng/dl in both groups at initiation and decreased to 3.0 and 2.1 respectively in 3 months(p>0.05).Castrate testosterone levels were reached in two groups after 3 months therapy( 9% and 6.7% of initial values respectively;p>0.05).The data is immature to assess the survival durations,but in median follow-up of 24 months,no difference in regard to PSA-progression was detected in the two groups(p=0.616). Conclusion: This randomized study of CPA and castration in patients with metastatic prostate cancer has not so far revealed any significant differences in progression-free survival.The initial efficacy and tolerability of monotherapy encourages us to comment that this therapy is safe and acceptable. Keywords: Prostate cancer,Cyproterone acetate,Castration,PSA-progression,Survival METASTATİK PROSTAT KANSERİNDE CYPROTERONE ACETATE VE KASTRASYON MONOTERAPİLERİNİN ETKİNLİĞİNİN KARŞILAŞTIRMASI: ÇOK MERKEZLİ BİR TÜRK ÜRO-ONKOLOJİ GRUBU ÇALIŞMASI ÖZET Amaç: İlerlemiş prostat kanserinde tibbi veya cerrahi kastrasyon ile CPA’yi karşılatırmak ve CPA’nin terapötik etkisini ortaya koymak. Gereç ve Yöntem: Ondokuz Üroloji Merkezi’ne başvuran T1-4N+MX veya T1-4NXM+ evreli prostat adenokanserli hastalar çalışmaya alınmıştır. Toplam 120 hasta, CPA 3X100mg/gün (Grup1) ve tıbbi veya cerrahi kastarasyon (Grup 2) gruplarına rastgele dağıtılmışlardır. Bu denemenin birincil son noktaları genel ve hastalığa-özel sağkalım olasılıklarıdır. Progresyonsuz sağkalım (PSA progresyon zamanı) ve testesteron düşüş hızı ikincil son noktalar olarak kabul edilmiştir.Progresyonsuz sağkalım olasılıkları Kaplan-Meier metoduyla hesaplanmış ve Logrank testiyle de sağkalım olasılıkları karşılaştırılmıştır. 75