Improved Outcomes with Advancements in High Intensity Focused Ultrasound Devices for the Treatment of Localized Prostate Cancer

Abstract

We evaluated the association between long-term clinical outcomes and morbidity with high intensity focused ultrasound. We included patients with stage T1c-T3N0M0 prostate cancer who were treated with Sonablate® (SB) devices during 1999 to 2012 and followed for more than 2 years. Risk stratification and complication rates were compared among the treatment groups (ie SB200/500 group, SB500 version 4 group and SB500 tissue change monitor group). Primary study outcomes included overall, cancer specific and biochemical disease-free survival rates determined using Kaplan-Meier analysis (Phoenix definition). Secondary outcomes included predictors of biochemical disease-free survival using Cox models. A total of 918 patients were included in the study. Median followup in the SB200/500, SB500 version 4 and the SB500 tissue change monitor groups was 108, 83 and 47 months, respectively. The 10-year overall and cancer specific survival rates were 89.6% and 97.4%, respectively. The 5-year biochemical disease-free survival rate in the SB200/500, SB500 version 4 and SB500 tissue change monitor group was 48.3%, 62.3% and 82.0%, respectively (p < 0.0001). The overall negative biopsy rate was 87.3%. On multivariate analysis pretreatment prostate specific antigen, Gleason score, stage, neoadjuvant androgen deprivation therapy and high intensity focused ultrasound devices were significant predictors of biochemical disease-free survival. Urethral stricture, epididymitis, urinary incontinence and rectourethral fistula were observed in 19.7%, 6.2%, 2.3% and 0.1% of cases, respectively. Long-term followup of patients with high intensity focused ultrasound demonstrated improved clinical outcomes due to technical, imaging and technological advancements.