Medium-term Outcomes after Whole-gland High-intensity Focused Ultrasound for the Treatment of Nonmetastatic Prostate Cancer from a Multicentre Registry Cohort

Background: High-intensity focused ultrasound (HIFU) is a minimally-invasive treatment for nonmetastatic prostate cancer.

Objective: To report medium-term outcomes in men receiving primary whole-gland HIFU from a national multi-centre registry cohort.

Design, setting, and participants: Five-hundred and sixty-nine patients at eight hospitals were entered into an academic registry.

Intervention: Whole-gland HIFU (Sonablate 500) for primary nonmetastatic prostate cancer. Redo-HIFU was permitted as part of the intervention.

Outcome measurements and statistical analysis: Our primary failure-free survival outcome incorporated no transition to any of the following: (1) local salvage therapy (surgery or radiotherapy), (2) systemic therapy, (3) metastases, or (4) prostate cancer-specific mortality. Secondary outcomes included adverse events and genitourinary function.

Results and limitations: Mean age was 65 yr (47-87 yr). Median prostate-specific antigen was 7.0 ng/ml (interquartile range 4.4-10.2). National Comprehensive Cancer Network low-, intermediate-, and high-risk disease was 161 (28%), 321 (56%), and 81 (14%), respectively. One hundred and sixty three of 569 (29%) required a total of 185 redo-HIFU procedures. Median follow-up was 46 (interquartile range 23-61) mo. Failure-free survival at 5 yr after first HIFU was 70% (95% confidence interval [CI]: 64-74). This was 87% (95% CI: 78-93), 63% (95% CI: 56-70), and 58% (95% CI: 32-77) for National Comprehensive Cancer Network low-, intermediate-, and high-risk groups, respectively. Fifty eight of 754 (7.7%) had one urinary tract infection, 22/574 (2.9%) a recurrent urinary tract infection, 22/754 (3%) epididymo-orchitis, 227/754 (30%) endoscopic interventions, 1/754 (0.13%) recto-urethral fistula, and 1/754 (0.13%) osteitis pubis. Of 206 known to be pad-free pre-HIFU, 183/206 (88%) remained pad free, and of 236 with good baseline erectile function, 91/236 (39%) maintained good function. The main limitation is lack of long-term data.

Conclusions: Whole-gland HIFU is a repeatable day-case treatment that confers low rates of urinary incontinence. Disease control at a median of just under 5 yr of follow-up demonstrates its potential as a treatment for nonmetastatic prostate cancer. Endoscopic interventions and erectile dysfunction rates are similar to other whole-gland treatments.

Patient summary: In this report we looked at the 5-yr outcomes following whole-gland high-intensity focused ultrasound treatment for prostate cancer and found that cancer control was acceptable with a low risk of urine leakage. However, risk of erectile dysfunction and further operations was similar to other whole-gland treatments like surgery and radiotherapy.