Focal High-intensity Focused Ultrasound Targeted Hemiablation for Unilateral Prostate Cancer: A Prospective Evaluation of Oncologic and Functional Outcomes

Background In selected patients with unilateral, organ-confined prostate cancer (PCA), hemiablation of the affected lobe might be feasible to achieve acceptable cancer control with fewer complications. Objectives To assess the oncologic and functional outcomes of focal high-intensity focused ultrasound (HIFU) hemiablation in unilateral organ-confined PCA. Design, setting and patients Single-center prospective evaluation of HIFU hemiablation for unilateral organ-confined PCA was performed from July 2009 through December 2013. Intervention Cancer localization was done with transrectal ultrasound-guided biopsy and multiparametric magnetic resonance imaging followed by HIFU hemiablation. Outcome measurement and statistical analysis Oncologic outcomes were analyzed with control biopsies and prostate-specific antigen (PSA) measurement. Functional outcomes were assessed with validated questionnaires for genitourinary symptoms. Results and limitations Of 71 HIFU hemiablation patients, 67 completed the study protocol. The mean age was 70.2 yr (standard deviation: 6.8 yr), and median PSA was 6.1 ng/ml (interquartile range [IQR]: 1.6-15.5 ng/ml). Median maximum cancer-core length was 3 mm (IQR: 2-10 mm), and total cancer length was 6.5 mm (IQR: 2-24 mm). Gleason score was 6 (3 + 3) in 58 patients (86.6%) and 7 (3 + 4) in 9 patients (13.4%). Median follow-up was 12 mo (IQR: 6-50 mo), and at 12 mo, 56 of 67 patients had a negative control biopsy in the treated lobe. At 3 mo, all patients were continent, and potency was maintained in 11 of 21 preoperatively potent patients (confidence interval, 0.18-0.69). Complications included 8% Clavien-Dindo grade 2 and 2.8% grade 3 events. Conclusions Focal HIFU hemiablation appears to achieve acceptable oncologic outcomes with low morbidity and minimal functional changes. Longer follow-up will establish future considerations. Patient summary This study showed that high-intensity focused ultrasound hemiablation in selected patients with unilateral organ-confined prostate cancer can be used for satisfactory cancer control with minimal effect on genitourinary functions.