Extracorporeal high-intensity focused ultrasound: Therapeutic alternative for renal tumors

Objectives: High intensity focused ultrasound (HIFU) is known to be used for the treatment of solid tumors in minimally invasive procedures. Transducers allowing for application of ultrasound from an extracorporeal focus have recently been developed. A review is provided of the development, physical principles, and current status of this therapy, and our early experience with it for the treatment of renal tumors is reported. Materials and methods: Extracorporeal HIFU is currently being used for the treatment of tumors (mainly hepatic, gynecological, and bone tumors), and has been started to be used for renal tumors with good results. A literature review (structured search in the online MEDLINE electronic base) of the physical principles of this treatment and its biological action is provided. The therapeutic procedure used in the first few patients with renal carcinoma successfully treated with HIFU at our hospital is reported. Results: This therapy has been successfully used to treat solid tumors at several centers in Europe, America, and Asia. Our center has a wide experience in treatment of gynecological tumors using extracorporeal HIFU, and has already treated renal tumors with no complications, although follow-up is still short. Conclusions: Extracorporeal use of this energy appears as a new option among non-invasive therapies for renal cancer in selected cases. A low complication rate has been noted, but much longer follow-up times are required for assessment of oncological results. (C) 2009 AEU. Published by Elsevier Espana, S.L. All rights reserved.