Does mpMRI guidance improve HIFU partial gland ablation compared to conventional ultrasound guidance? Early functional outcomes and complications from a single center

Background: Focal therapy (FT) for localized prostate cancer (PCa) treatment is raising interest. New technological mpMRI-US guided FT devices have never been compared with the previous generation of ultrasound-only guided devices. Materials and Methods: We retrospectively analyzed prospectively recorded data of men undergoing FT for localized low- or intermediate-risk PCa with US- (Ablatherm®-2009 to 2014) or mpMRI-US (Focal One®-from 2014) guided HIFU. Follow-up visits and data were collected using internationally validated questionnaires at 1, 2, 3, 6 and 12 months. Results: We included n=88 US-guided FT HIFU and n=52 mpMRI-US guided FT HIFU respectively. No major baseline differences were present except higher rates of Gleason 3+4 for the mpMRI-US group. No major differences were present in hospital stay (p=0.1), catheterization time (p=0.5) and complications (p=0.2) although these tended to be lower in the mpMRI-US group (6.8% versus 13.2% US FT group). At 3 months mpMRI-US guided HIFU had significantly lower urine leak (5.1% vs. 15.9%, p=0.04) and a lower drop in IIEF scores (2 vs. 4.2, p=0.07). Of those undergoing 12-months control biopsy in the mpMRI-US-guided HIFU group, 26% had residual cancer in the treated lobe. Conclusion: HIFU FT guided by MRI-US fusion may allow improved functional outcomes and fewer complications compared to US- guided HIFU FT alone. Further analysis is needed to confirm benefits of mpMRI implementation at a longer follow-up and on a larger cohort of patients.