Clinically significant localized prostate cancer (PCa) is currently treated using whole-gland therapy. This approach is effective but is associated with genitourinary and rectal side-effects. Focal therapy of PC has been proposed as an alternative. The aim of the study was to determine the oncologic and functional outcomes of focal high-intensity focused ultrasound (HIFU) therapy for PCa.
This was a single-centre prospective study in which 75 men were treated between 04/2014 and 04/2018. Multiparametric magnetic resonance imaging (mpMRI) and transperineal template saturation prostate biopsies (TTSPB) were performed to localise PCa, followed by focal ablation using HIFU. The primary endpoint was detection of clinically significant prostate cancer (Gleason score ≥7, csPCa) at the 6 months follow-up TTSPB. Of secondary interest were the genitourinary side effects.
The median age was 67 yrs (interquartile range [IQR] 60-71) and prostate-specific antigen (PSA) was 5.87 ng/ml (4.64-7.44). There were five (6.7%) low-risk and 70 (93.3%) intermediate-risk cancers. CsPCa was detected in 41% (95% CI: 30.3%- 53.0%) of men undergoing biopsy at 6 months with a median sampled core number of 44 (IQR 36-44). PSA (OR 1.17 [0.49-2.85], p=0.71) and mpMRI (sensitivity 14.3% [6.7-31.5%]) performed poorly in prediction of positive biopsies. Pad-free continence and erections sufficient for penetration were preserved in 63/64 (98.4%) and 31/45 (68.9%) patients, respectively.
Focal therapy using HIFU leads to a low rate of genitourinary side-effects. Follow-up biopsy of the treated and untreated prostate remains the only modality to adequately select men in need of early salvage treatment.