Results and Side Effects of High-Intensity Focused Ultrasound in Localized Prostate Cancer

Abstract

At the time of diagnosis, prostate cancer is organ confined in 70% of the cases. A quarter of these patients undergo local therapy (surgery/radiation); 75% risk disease progression by "watchful waiting" or systemic side effects through hormonal ablation. Local high-intensity focused ultrasound (HIFU), as minimal invasive tissue coagulation (85°C), ablates prostatic tissue with high precision. Since April 1996, 184 patients have undergone 232 sessions of transrectal HIFU therapy (average 90 min) under spinal anesthesia at 2.25/3.0 MHz, 50 W, and a penetration depth of 25 mm. The follow-up serum prostate specific antigen (PSA) concentration, sextant biopsies, International Prostate Symptom Score (IPSS), quality of life measures (QoL), and complaint registration provide the foundation for this clinical evaluation. Follow-up sextant biopsies (an average of 1.9) showed 80% of the patients to be cancer free. In men with residual cancer, the tumor mass was reduced more than 90%. The PSA nadir in 97% was <4 ng/mL, including 61% with values <0.5 ng/mL. After primary HIFU, no severe side effects (fistula, second or third grade incontinence, rectal mucosal burns) occurred. All patients had a suprapubic tube (average 29 days), and 33% needed a transurethral debris resection averaging 7 g. They were discharged within 23 hours. According to the short-term follow-up transrectal HIFU enables minimal invasive local prostate tissue ablation with high rates of negative biopsies, low PSA nadir, and low complication rate.