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

Abstract Objective High-intensity focused ultrasound (HIFU) is currently being used to treat solid tumors in minimally invasive procedures. Transducers allowing for application of ultrasound from an extracorporeal focus have recently been developed. A review of the development, physical principles, and current status of this therapy is provided, and our early experience in treatment of renal tumors with this procedure 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 HIFU has been successfully used to treat solid tumors at several centers in Europe, America, and Asia. Our center has a wide experience in the 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 reported, but much longer follow-up times are required for assessment of oncological results.