High-intensity focused ultrasound for focal therapy

Ariel A. Schulman, Kae Jack Tay, Cary N. Robertson, Thomas J. Polascik

Progress in imaging, fusion software, and ablative modalities has fostered growth of the latest image-guided generation of high-intensity focused ultrasound (HIFU) for focal treatment of prostate cancer. Although early reports are encouraging, important questions remain regarding candidate selection, treatment, and outcomes. We review contemporary considerations for the use of HIFU for focal treatment of primary and radio-recurrent prostate cancer. HIFU has been used to treat prostate cancer for over two decades. More recently, stage migration from screening and improvements in pelvic imaging and fusion technology has resulted in wider clinical application of focal HIFU as a first-line treatment for localized prostate cancer. Advanced imaging has also improved targeting for focal salvage therapy of radio-recurrent disease. Proponents point to the minimally invasive nature, limited morbidity profile, and ability to perform retreatments in the future. Critics emphasize positive post-treatment biopsies, nonuniform treatment protocols, and absence of long-term follow-up. Thus, a review of clinical considerations and recently published data is warranted. Recent advances have strengthened support for the use of focal HIFU. Although HIFU has great potential, it must be applied judiciously, maintaining appropriate oncologic principles in the setting of standardized trials to determine its true clinical value.