Evolution and outcomes of 3 MHz high intensity focused ultrasound therapy for localized prostate cancer during 15 years.

Purpose: We describe the long-term cancer control and morbidity of high intensity focused ultrasound with neoadjuvant transurethral resection of the prostate, the risk of metastatic induction by transurethral prostate resection, and the evolution of high intensity focused ultrasound application and technology with time.

Materials And Methods: A prospective Harlaching high intensity focused ultrasound database was searched for patients with primary localized prostate cancer (T1-2, N0, M0, PSA at first diagnosis less than 50 ng/ml) and followup longer than 15 months. Those patients with previous long-term androgen deprivation therapy, locally advanced prostate cancer or any therapy influencing prostate specific antigen were excluded from study. All patients were treated completely with an Ablatherm® high intensity focused ultrasound device. Evaluation was performed in aggregate, and by stratification according to cohort group, risk group (D'Amico criteria), prostate specific antigen nadir and Gleason score. The Phoenix definition was used for biochemical failure. Statistical analysis was performed using the Kaplan-Meier method, and univariate and multivariate analysis was performed using a Cox model.

Results: Of 704 study patients 78.5% had intermediate or high risk disease. Mean followup was 5.3 years (range 1.3 to 14). Cancer specific survival was 99%, metastasis-free survival was 95%, and 10-year salvage treatment-free rates were 98% in low risk, 72% in intermediate risk and 68% in high risk patients. Prostate specific antigen nadir and Gleason score predicted biochemical failure, and side effects were moderate. The high intensity focused ultrasound re-treatment rate has been 15% since 2005.

Conclusions: Long-term followup with high intensity focused ultrasound therapy demonstrated a high overall rate of cancer specific survival and an exceptionally high rate of freedom from salvage therapy requirements in low risk patients. Advances in high intensity focused ultrasound technology and clinical practice as well as the use of neoadjuvant transurethral prostate resection allow the complete treatment of any size prostate without inducing metastasis.