Ultrasound- and MR-guided focused ultrasound surgery for prostate cancer

Abstract

Prostate cancer (PC) is one of the most frequently diagnosed cancers in men. There are a number of treatment options for PC with a different therapeutic approach between USA and Europe. Radical prostatectomy is one of the most used therapies but focal gland therapy is an emerging approach, especially for localized tumors. In this scenario, high intensity focused ultrasound (HIFU) has been incorporated in certain medical association guidelines. HIFU has been employed for about 10 years especially for localized PC. Results are promising with a 5-year biochemical survival rate ranging from 45% to 84%. Collateral events are rare and HIFU retreatment is not common. Magnetic resonance guided focused ultrasound surgery (MRgFUS) was recently presented as a method for ablation with focused ultrasound under magnetic resonance imaging guidance. It has the advantage of improved targeting and real time temperature monitoring but only a few studies have been conducted with human patients. The aim of this review is to describe the current status of HIFU and MRgFUS in the therapy of PC.

Keywords: High intensity focused ultrasound; Magnetic resonance guided focused ultrasound surgery; Prostate cancer.

Figure 1

Magnetic resonance guided focused ultrasound surgery suite at the University of Chicago. A: Magnetic resonance guided focused ultrasound surgery (MRgFUS) probe and phase array; B: Focused picture of MRgFUS phased array transducer.

Figure 2

Magnetic resonance guided focused ultrasound surgery of human prostate. A: Pre-sonification scan, catheter is visible in prostate urethra and transrectal probe is present in the rectum, filled by water. Hypointense focus in the left peripheral zone represents patient`s biopsy proven prostate cancer; B, C: Post-contrast T1-weighted images through prostate demonstrates non-enhancing ablation defect in the left peripheral zone.