[11C]Choline PET/CT predicts survival in hormone-naïve prostate cancer patients with biochemical failure

Objectives Preliminary results indicate that positive [11C]choline PET/CT (PET/CT) may predict prostate cancer (PCa)-specific survival in patients that develop biochemical failure during anti-androgenic therapy (ADT). Aim of the study was to assess whether PET/CT predicts survival in PCa patients with biochemical failure that never received ADT.

Methods This retrospective study included 302 patients with PCa treated with radical prostatectomy that underwent PET/CT from December 2004 to July 2007 owing to biochemical failure. PCa-specific survival was defined as the time interval between radical prostatectomy and PCa-specific death or censoring.

Results Median follow-up was 7.4 yrs (range: 1.9 - 18.8 yrs). PET/CT was positive in 101/302 (33%) patients. In patients with PET/CT+ median PCa-specific survival was 12 yrs (95% CI, 7.7-16.4 yrs). In patients with PET/CT- neither median survival nor the 25th percentile were achieved owing to the low number of PCa-specific deaths (n=5) (Chi-Square=25.7, P<0001). At multivariate analysis statistical significance was obtained for PET/CT (HR =6.39, 95% CI, 2.15-19.03, P=0.001) and Gleason score > 7 (HR=3.33, 95% CI, 1.18-9.37, P=0.023). Bivariate analysis (n=76) showed that PET/CT predicted PCa-specific survival (HR=6.21, 95% CI, 1.31-29.37, P=0.021), while PSADT did not (HR=0.93, 95% CI, 0.84-1.02, P=0.126). The 5-year PCa-specific survival probability after PET/CT was 82.9% (95% CI, 78.6%-87.2%) in patients with PET/CT- and 44.7% (95% CI, 39.5%-49.9%) in patients with PET/CT+. Ancillary analysis showed that PET/CT predicts PCa-specific survival after PET/CT with very similar statistical power.

Conclusions PET/CT+ after biochemical failure predicts PCa-specific survival in hormone-naïve PCa patients. These results further suggest PET/CT should be more widely used for prognostic stratification in the follow-up of PCa patients.