P189 Role of high intensity focused ultrasound (HIFU) in treating cancerous lesions of the hepatobiliary system

Aims High intensity focused ultrasound (HIFU) is an emerging non-invasive, targeted treatment of malignancy. This review aims to explore the efficacy, safety and optimal technical parameters of HIFU to treat cancerous lesions of the hepatobiliary system. Methods A systematic search of the English literature was performed until December 2018, interrogating Pubmed, Embase and Cochrane Library databases. The following key-words were input in various combinations: ‘HIFU’, ‘High intensity focussed ultrasound’, ‘Hepatobiliary’, ‘Liver’, ‘Cancer’ and ‘Carcinoma’. Extracted content included: Application type, Exposure parameters, Patient demographics, and Treatment outcomes. Results Twenty-two articles reported on the clinical use of HIFU in 845 individuals to treat cancerous liver lesions. Nineteen series detailed the use of HIFU to treat hepatocellular carcinoma. Mean tumour size was 5.1 cm. Across all studies, HIFU resulted in complete tumour ablation in 51.68%. Data on technical parameters and the procedural structure was very heterogeneous. Eight studies described the use of HIFU alongside other modalities including TACE, RFA and PEI; 58.72% of which resulted in complete tumour ablation. Most common complications were skin burns(17.16%), local pain(5.56%) and fever(1.42%). Conclusions HIFU is a safe and well-tolerated treatment modality for cancerous lesions of the hepatobiliary system. Combining HIFU with other ablative therapies, particularly TACE, increases the efficacy without increasing complications. Future human clinical studies are required to determine the optimal treatment parameters, better define outcomes and explore the risks and benefits of combination therapies.