WCE 2017: Single-session Primary High-intensity Focused Ultrasonography (HIFU) as a Treatment for Localized Prostate Cancer: Predicting Disease-free Survival by Risk Stratification

Vancouver, Canada (UroToday.com) Dr. Jen Hoogenes, clinical urology researcher from the McMaster University, presented data on the use of high-intensity focused ultrasonography (HIFU) to treat localized prostate cancer (PCa). As an introduction to his talk, he explained how HIFU utilizes ultrasound waves to cause tissue ablation via coagulative necrosis, inertial cavitation, and can potentially delay immune response to the treatment area. He also mentioned how conventional treatment options of radical prostatectomy and external beam radiation therapy for localized prostate cancer are often associated with post-treatment morbidities including incontinence and erectile dysfunction. The aim of their study was to determine significant predictors of disease-free survival post-HIFU treatment and evaluate the efficacy of HIFU as an alternative treatment for PCa that is less invasive and may have less postoperative complications. 

Dr. Hoogenes and her team retrospectively analyzed clinical data of an initial group of 741 consecutive patients who underwent a single-session HIFU treatment for PCa. Patients were excluded if they previously received treatment for their PCa, or did not complete their six-month follow up appointments. Treatment failure was defined as patients who underwent salvage therapy such as salvage radiation, prostatectomy, or repeat HIFU. Other variables such as pre-treatment PSA, PSA density, Gleason grade, prostate volume, and D’Amico risk score were collected and statistically analyzed with log-rank tests to evaluate the progressive disease-free status to determine the impact of treatment success. 

A total of 521 patients of the 741 met the inclusion criteria and comprised the final sample for analysis. Information such as demographics and clinical characteristics were collected for each patient. 91.5% had a Gleason grade between 5 and 7, and 59% had an intermediate D’Amico score. They also found the mean PSA was 7.7 ± 5.6 and mean PSA density was 0.33 ± 0.28. 52 patients experienced treatment failure, and of these 52, 31 patients sought salvage therapy.

In conclusion, Dr. Hoogenes and her team determined that HIFU demonstrated promising efficacy for the treatment for PCa. She ended her presentation by proposing a future direction of the study could be to utilize larger, multi-center prospective trials to investigate efficacy, functional outcomes, postoperative complications, and quality of life following HIFU treatment for PCa.

Presented by: Jen Hoogenes 

Authors: Bobby Shayegan, Taehyoung Lee, Joshua Hwang, William Orovan, Jen Hoogenes
Affiliation: McMaster University, Hamilton, Ontario, Canada

Written by Cyrus Lin, Department of Urology, University of California-Irvine at the 35th World Congress of Endourology– September 12-16, 2017, Vancouver, Canada.