High intensity focused ultrasound (HIFU) applied to hepato-bilio-pancreatic and the digestive system—current state of the art and future perspectives

Abstract

Background: High intensity focused ultrasound (HIFU) is emerging as a valid minimally-invasive imageguided treatment of malignancies. We aimed to review to current state of the art of HIFU therapy applied to the digestive system and discuss some promising avenues of the technology.Methods: Pertinent studies were identified through PubMed and Embase search engines using the following keywords, combined in different ways: HIFU, esophagus, stomach, liver, pancreas, gallbladder, colon, rectum, and cancer. Experimental proof of the concept of endoluminal HIFU mucosa/submucosa ablation using a custom-made transducer has been obtained in vivo in the porcine model. Results:Forty-four studies reported on the clinical use of HIFU to treat liver lesions, while 19 series were found on HIFU treatment of pancreatic cancers and four studies included patients suffering from both liver and pancreatic cancers, reporting on a total of 1,682 and 823 cases for liver and pancreas, respectively. Only very limited comparative prospective studies have been reported. Conclusions:Digestive system clinical applications of HIFU are limited to pancreatic and liver cancer. It is safe and well tolerated. The exact place in the hepatocellular carcinoma (HCC) management algorithm remains to be defined. HIFU seems to add clear survival advantages over trans arterial chemo embolization (TACE) alone and similar results when compared to radio frequency (RF). For pancreatic cancer, HIFU achieves consistent cancer-related pain relief. Further research is warranted to improve targeting accuracy and efficacy monitoring. Furthermore, additional work is required to transfer this technology on appealing treatments such as endoscopic HIFU-based therapies.Keywords: High intensity focused ultrasound (HIFU); liver cancer; pancreatic cancer; miniature HIFU delivery system; endoluminal applications of HIFU; mucosa and submucosal ablations using HIFU

Laser ablation of the biliary tree:in vivoproof of concept as potential treatment of unresectable cholangiocarcinoma

“…However, no data were reported regarding its specificity and sensibility in detecting post-procedural cholangiocarcinoma residual cells. Further studies could be required to assess its potentiality as a post-LA evaluation device [43,44].…”

Ablative Techniques for Image-Guided Thermal Ablation

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The Possibilities of Modern Methods of Ablation in Non-Resectable Locally Advanced Pancreatic Cancer

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