986 Prognostic Predictors in Prostate Cancer Cases with Biochemical Progression after Surgery Treated with Intermittent Androgen Deprivation (IAD)

INTRODUCTION AND OBJECTIVES: To define characteristics of the first cycle of IAD that would predict for outcomes in a long term follow-up.The end-points of the trial was time to clinical progression(CP)and time to castration resistance PC(CRPC). METHODS: Eighty-four cases were included in the study. In all cases, after an initial induction period, an acceptable nadir to switch from on-to-off-phase of IAD was considered to be a serum PSA of less than 1.0 ng/ml. As possible predictors for time to CP and CRPC we analyzed pretreatment parameters such as age,Gleason Score,serum PSA,testosterone and Chromogranina A(CgA)levels and characteristics from the first cycle of IAD. RESULTS: Mean follow-up during IAD was 88.69 16.74 months;29.77% of patients developed CRPC and 14.28% of cases showed a CP with a mean time of 88.40 14.34 months and 106.50 20.65 months respectively.At the univariate and multivariate analysis the PSA nadir during the first on-phase period and the first off-phase interval resulted significant and independent predictors(p 0.001)of the time to CRPC and CP.In particular for cases with a PSA nadir 0.4 ng/ml and for those with an off-phase interval 24 weeks,the risk of CRPC and CP during IAD was 2.7-2.5 and 3.0-3.1 times that for patients with a PSA nadir 0.1 ng/ml and with an off-phase interval 48 weeks respectively. CONCLUSIONS: Cases with BP after RP selected to IAD that show at the first cycle a PSA nadir 0.1 ng/ml and a off-phase interval 48 weeks, are the best candidate for long IAD treatments without the development of CRPC or CP.