Focal Magnetic Resonance Guided Intensity Focused Ultrasound Treatment of Low Risk Prostate Cancer: A Phase I Trial. Alexandr Nosov, Sergey Kanaev, Georg Gafton, Vladimir Turkevich, Maxim, Andrey Vorobiev. Petrov Research Institute of Oncology, St. Petersburg, Russia.

Identify and localize in prostate unilateral disease PSA multiparametric magnetic resonance imaging (MMRI) (T2-weighted, dynamic contrast enhanced, diffusion-weighted, spectroscopy) template transperineal prostate mapping biopsies.

Appraisal genitourinary side effects and quality of life Posttreatment PSA MMRI questionnaires were performed every 3 months biopsies were performed at 6 months.

RESULTS 5 men underwent focal magnetic resonance guided intensity focused ultrasound treatment 60.6 years (range 49 to 73) PSA 4.8 ng/ml (range 2.2 to 10) Gleson < or = 6 1 positive biopsy core and concurrence of MMRI

RESULTS After the treatment 100% of men were pad- free and leak-free continence starting the first day. Four men had PSA decreased to 1.5 ng/ml in 6 months One man had PSA increased from 10 ng/ml to 13,5 ng/ml

CONCLUSIONS The results of our research prove the necessity of the further evaluation of MRI guided focal therapy as a strategy to decrease some of the harms and costs associated with whole gland treatments