EAU 2020: Midterm Oncological Results of Focal Therapy: HIFU Focal Ablation

(UroToday.com) The focal therapy for prostate cancer thematic session at the 2020 European Association of Urology (EAU) Virtual meeting included Dr. Clément Orczyk discussing focal ablation with high-intensity focus ultrasound (HIFU).

Dr. Orczyk’s team at University College London has a prospective cohort of 1,032 men that have been treated with hemi-gland and focal HIFU.1 These men had significant unilateral disease, either GG1 & GG2 or GG2 & GG3 prostate cancer. Their group does not treat GG1 prostate cancer with HIFU. Furthermore, there must be a concordant mpMRI lesion and insignificant prostate cancer outside of the anterior zone is permitted. The template of ablation has changed over time and now includes a 5-9 mm margin around a lesion seen on mpMRI; retreatment is also permitted. Monitoring of these patients includes a combination of prostate-specific antigens (PSA) and mpMRIs, with PSAs every three months in order to assess a PSA nadir. Per protocol at one year includes an mpMRI +/- a biopsy (targeted +/- transperineal mapping), and systematic mpMRIs are repeated at 3, 5, and 10 years. A for-cause mpMRI is performed when the PSA significantly increases over the PSA nadir.

Among the 1,032 patients included, 63.4% were GG2, median baseline PSA was 7 ng/dL (IQR 4.9-9.7), median prostate volume was 36.5 cc (IQR 28-48), and 92.4% of tumors were visible on mpMRI. In their cohort, the median follow-up is currently 36 months (IQR 11-64 months; range 0-131 months). Treatment-related complications included 9.6% of patients requiring an endoscopic procedure (Clavien-Dindo Grade IIIb), 0.12% of patients suffering a rectourethral fistula (Grade IIIa), and 8.5% of patients having a urinary tract infection (Grade I).

With regards to oncologic outcomes, any cancer biopsy free survival (all Gleason grade [GG]) is as follows:

  • 12-months: 90.8%
  • 24- months: 79.3%
  • 60-months: 53.5%
  • 96-months: 40.6%
cancer biopsy free survival

Overall, 26.3% of patients required retreatment, with the majority of these patients having retreatment HIFU (71.2%). The median time to retreatment was 26 months (IQR 13-46). Additional outcomes included: (i) time to radical treatment (median 36 months, IQR 14-60), (ii) systemic therapy rate (1.9%), (iii) biochemical recurrence after radiotherapy rate (7%), and (iv) distant metastasis rate (1.6%).

Presented by: Clément Orczyk, MD, PhD, Associate Professor of Urology, University College London Hospitals NHS Foundation Trust, London, United Kingdom

Written by: Zachary Klaassen, MD, MSc, Assistant Professor of Urology, Georgia Cancer Center, Augusta University/Medical College of Georgia, Augusta, Georgia, Twitter: @zklaassen_md at the Virtual 2020 EAU Annual Meeting #EAU20, July 17-19, 2020

References: 

1. Stabile, Armando, Clement Orczyk, Feargus Hosking‐Jervis, Francesco Giganti, Manit Arya, Richard G. Hindley, Louise Dickinson et al. "Medium‐term oncological outcomes in a large cohort of men treated with either focal or hemi‐ablation using high‐intensity focused ultrasonography for primary localized prostate cancer." BJU international 124, no. 3 (2019): 431-440.