Whole‐gland salvage high‐intensity focused ultrasound therapy for localized prostate cancer recurrence after external beam radiation therapy

Abstract

Whole-gland high-intensity focused ultrasound (HIFU) has been used as salvage therapy for local recurrence following external beam radiation therapy for decades. This article describes the use of the Sonablate 500 HIFU system in the salvage setting. An evaluation was performed of a consecutive group of men with biochemical failure after external beam radiation therapy with histologically proven local recurrence and bone-scan and pelvic magnetic resonance imaging to exclude macroscopic metastases, and who chose to have whole-gland salvage HIFU (Sonablate 500) at 2 centers (3 expert HIFU surgeons at each center). The modified Clavien system was used to categorize adverse events and validated questionnaires for functional outcomes. Progression following HIFU treatment was defined as ASTRO-Phoenix criteria (prostate serum antigen [PSA] >nadir+2 ng/mL) and/or a positive biopsy and/or start of hormone therapy. Eighty-four men underwent whole-gland salvage HIFU (2004-2009). Median age, pretreatment serum PSA, and biopsy Gleason score was 68 years (range, 64-72 years), 4.3 ng/mL (range, 1.9-7.9 ng/mL), and 7 (range, 6-7), respectively. Mean follow-up was 19.8 months (range, 3.0-35.1 months). After salvage HIFU, 62% of the men were pad-free and leak-free. Mean International Index of Erectile Function-5 point score fell from 8.8 to 4.7 (P < .001). International Prostate Symptoms Score and RAND-SF36 scores were not affected. Two men developed rectourethral fistulae after 1 salvage procedure. A further 2 fistulae occurred in the 6 men undergoing a second salvage HIFU. Intervention for bladder outlet obstruction was needed in 20% (17 of 84 patients). If PSA nonresponders were included, 1- and 2-year progression-free survival rates were 59% (50 of 84 patients) and 43% (36 of 84 patients), respectively. If PSA nonresponders were excluded, 1- and 2-year progression-free survival rates were 62% (48 of 77 patients) and 48% (37 of 77 patients), respectively. Salvage whole-gland HIFU is a high-risk procedure. Although its use in early cancer control is promising, strategies to better identify metastatic disease prior to salvage therapy and reduce local toxicity are needed to improve on this.