Correlation of 11c-choline PET-CT with time to treatment and disease-specific survival in men with recurrent prostate cancer after radical prostatectomy.

123 Background: Restaging with PET-CT in biochemical recurrent prostate cancer after prostatectomy shows a higher frequency of (false) negative cases compared to restaging after EBRT. It is uncertain if this reflects low volume of disease and/or low grade as biopsies fail to prove recurrent cancer in 50% of cases. We followed the clinical course of men with recurrent prostate cancer (PCa) after radical prostatectomy and investigated treatment and survival. PET-CT data were correlated with clinical data, PSA kinetics and disease specific and overall survival. We also studied relative survival comparing an age matched group from the Central Dutch Statistical Office (CBS). METHODS 64 patients underwent 11C-Choline PET-CT on PSA relapse. All patients were initially treated with radical prostectomy and reached PSA nadir of <0.1ng/mL. Recurrent disease was defined as PSA <0.4ng/mL after nadir. Patients were either treated with watchful waiting, adjuvant radiotherapy and/ or androgen deprivation therapy based on individual assesments by the treating urologists. Chi-square, log-rank and Mann-Whitney-U tests were used to study this population Results: The 64 patients had median PSA of 1.4ng/mL. Median follow-up period of patients was 50 (6-124) months. Ten patients died during the course of follow-up of which 5 due to metastasized PCa. No significant differences were seen in age, time to recurrence, total PSA at recurrence and PET-CT results. Patients with abnormal PET had higher PSAVel (median 3.09 ng/mL/yr vs 10.17, p= 0.002) and and shorter PSADT (med 4.83 mo vs 0.53, p= 0.016). Median time to treatment was significantly lower in the PET-CT negative group. Age of patients at death from the whole group did not differ from the age of death in an age matched group. Disease specific survival was significantly higher in the PET-CT negative group (p0.05). CONCLUSIONS A negative 11C-Choline PET-CT correlated with a higher disease specific survival and a lower treatment rate. Overall survival of the group was equal to the age matched cohort. No significant financial relationships to disclose.