MP15-06: Risk of adverse radical prostatectomy outcomes in patients diagnosed with IUSP &[le] 2 prostate cancer on MRI/TRUS fusion biopsy

Claudia Kesch*, Vlad Pantea, Essen, Germany, Timo Soeterik, Nieuwegein-Utrecht, Netherlands, Alessandro Marquis, Turin, Italy, Giulia La Bombarda, Allesandro Morlacco, Padova, Italy, Francesco Barletta, Milan, Italy, Felix Preisser, Frankfurt, Germany, Fabio Zattoni, Padova, Italy, Giancarlo Marra, Turin, Italy, Roderik C. N. van den Bergh, Nieuwegein-Utrecht, Netherlands, Jan Philipp Radtke, Boris Hadaschik, Essen, Germany, Giorgio Gandaglia, Milan, Italy

Introduction: To avoid overtreatment, active surveillance (AS) is recommended for prostate cancer (PC) patients with low- to favorable intermediate-risk features. However, previous studies based on 12-core transrectal ultrasound (TRUS) biopsy have demonstrated high upgrading rates (up to 70%)  at radical prostatectomy (RP) in men potentially suitable for AS. We aim at exploring rate and risk factors for adverse pathologic outcomes in patients with multiparmetric magnetic resonance imaging (mpMRI)/TRUS fusion biopsy confirmed ISUP =  2 PC.

Methods: Multicentre, retrospective analysis of 477 consecutive patients with ISUP =  2 PC on mpMRI/TRUS fusion biopsy treated with RP. Adverse outcomes (AO) were defined as any ISUP upgrading, upgrading to ISUP = 3, =pT3 at RP, any AO (=ISUP upgrading to = 3 and/or =pT3 and/or N1) or biochemical recurrence (BCR) in men with available follow-up (n=327).  Rates of AO were calculated for the overall cohort, biopsy ISUP 1 (n=149) and biopsy ISUP 2 (n=328) PC. Groups were compared using Qui-square test.  Logistic regression was used to determine predictive factors.

Results: The overall rates of ISUP upgrading, ISUP upgrading to = 3, =pT3 on RP and any AO were 39%, 21%, 32% and 43%, respectively. Compared to biopsy ISUP 2, men with biopsy ISUP 1 PC experienced more  frequently ISUP upgrading (27% vs. 67%, p<0.001), but less ISUP upgrading to = 3 (27% vs. 10%, p<0.001) and any AO (48% vs. 32%, p=0.001). No differences were recorded for =pT3 on RP (34% vs. 26%, p=0.052). PSA density, PIRADS score on mpMRI, number of positive targeted biopsy (TB) cores, ISUP of TB cores, overall number of biopsy cores and positive biopsy cores were all predictive factors for ISUP upgrading to = 3, =pT3 at RP as well as for any AO. Neither PSA nor positive digital rectal examination significantly predicted AOs. Median time of follow-up was 12 months. The 1-year BCR-free survival was 94%. No significant differences in BCR rates were observed comparing men with biopsy ISUP 1 and biopsy ISUP 2 (5% vs. 7%, p=0.518). Positive TB cores, ISUP at RP, ISUP upgrading, ISUP upgrading to = 3, =pT3 on RP and any AO were all predictive for BCR.

Conclusions: In men with mpMRI/TRUS fusion biopsy confirmed ISUP =  2 PC adverse outcomes at RP are still frequent. When counseling patients regarding AS, especially PSA density, ISUP, mpMRI findings and number of positive biopsy cores should be taken into account to identify the men at higher risk of AO.

Source of Funding: None