Research findings presented at the 37th Annual European Association of Urology Congress in Amsterdam, The Netherlands, may give clinicians a better sense of the oncologic outcomes resulting from focal treatment of localized prostate cancer using high-intensity focused ultrasound (HIFU).
In a retrospective study, investigators propensity-score matched 137 HIFU partial ablation patients with 548 radical prostatectomy (RP) patients and 84 HIFU total ablation patients with 336 RP patients. At 30 months after treatment, the HIFU partial ablation group had a significantly lower failure-free survival (FFS) rate compared with the matched RP group (77.8% vs 91.4%), Changhee Ye, MD, of Seoul National University Bundang Hospital in Seongnam, South Korea, and colleagues reported. The partial ablation group also had a significantly lower salvage-free survival (SFS) rate compared with the matched RP group (69.8% vs 97.7%). The 30-month FFS and SFS rates did not differ significantly between the HIFU total ablation and RP groups.
With respect to functional outcomes, both HIFU groups had significantly better erectile function compared with the RP groups. Scores on the International Index of Erectile Function (IIEF)-5 instrument at 6 months were 9.15 for the HIFU partial ablation group compared with 5.78 in the matched RP group. The scores were 11.24 for the HIFU total ablation group compared with 9.78 in the matched RP group. Both HIFU groups and the RP patients did not differ significantly with respect to International Prostate Symptom Score.
Investigators propensity-score matched patients for age at treatment, body mass index, clinical T stage, diabetes, hypertension, use of neoadjuvant therapy, Gleason grade group, prostate volume, and pre-treatment PSA level. They defined failure-free survival as the presence of grade group 2 cancer at post-treatment biopsy in the HIFU-treated patients and biochemical recurrence in the RP recipients.
Separately, Basil Kaufmann, MD, of University Hospital Zurich in Switzerland, and colleagues reported on a prospective single-center study of 91 patients who underwent HIFU for localized prostate cancer showing that, at follow-up biopsy at 36 months, 48 (53%) had evidence of significant cancer, 22 (24%) had no cancer, and 21 (23%) refused a follow-up biopsy.
At 36 months, the cancer-specific survival rate was 100%, and 83% of patients remained free from radical treatment, according to the investigators. Urinary symptoms and bowel assessment returned to baseline questionnaire scores within 3 months and quality of life scores were the same as before therapy, the investigators reported.
“Non-whole-gland HIFU treatment for localized prostate cancer shows excellent functional outcomes with adequate prostate cancer control in the mid-term,” the authors concluded in a study abstract.
The study only included treatment-naïve patients with Gleason 4+3 cancer or less, a PSA level of 15 ng/mL or less, and a life expectancy of more than 10 years. Of the 91 patients, 67% had Grade Group 2, 26% had Grade Group 3, and 7% had Grade Group 1 prostate cancer.
In another study, HIFU focal treatment of localized prostate cancer was associated with a 5-year oncologic control rate of nearly 54%, according to results reported by Claire Deleuze, MD, of Institut Mutualiste Montsouris in Paris, France, on behalf of her team. The study included 256 patients who underwent HIFU treatment from 2009 to 2019 for low- and intermediate-risk prostate cancer. Investigators performed systematic biopsies after 1 year and/or in case of suspected failure. They defined failure as any positive biopsies in the treated area.
Patients had a median age of 68.1 years and a median follow-up of 5.2 years. The investigators identified treatment failure in 118 patients (46.2%). Of these, the biopsy revealed clinically significant cancer in 66 cases (55.6%). The failure-free survival rate was 67.3% and 53.8% at 2 and 5 years, respectively.
At 5 years, the erectile dysfunction and urinary incontinence rates were 7.0% and 1.6%, respectively.
Ye C, Jung G, Kim H, et al. Partial ablation and total ablation with high intensity focused ultrasound (HIFU) compared to radical prostatectomy (RP): A propensity score matched study. Presented at EAU 2022, July 1-4, 2022, Amsterdam, The Netherlands. Abstract A0309.
Kaufmann B, Raess E, Donati O, et al. 3-year oncological outcome of a prospective trial using focal therapy for localized prostate cancer with high-intensity focused ultrasound. Presented at: EAU 2022, July 1-4, 2022, Amsterdam, The Netherlands. Abstract A0310.
Deleuze C, Barret E, Fregeville A, et al. 5-year outcomes of high-intensity focused ultrasound (HIFU) treatment of localised prostate cancer. Presented at: EAU 2022, July 1-4, 2022, Amsterdam, The Netherlands. Abstract A0313.