Research progress and clinical evaluation of histotripsy: a narrative review

BACKGROUND AND OBJECTIVE: As a soft-tissue noninvasive ablation technology, high-intensity focused ultrasound (HIFU) has been widely used to treat many clinical diseases. However, traditional HIFU, based on thermal effects, has a high local working temperature, which may cause thermal damage to surrounding tissues and reduce the therapeutic effect. Based on the cavitation effect of HIFU, histotripsy can mechanically destroy the cells in the target lesion. This paper aims to explain the mechanism of histotripsy, summarize the research progress of animal models for clinical evaluation and clinical application, and analyze the advantages and limitations of histotripsy. METHODS: Literature published from January 2006 to March 2022 was retrieved from the PubMed database. We reviewed these articles to examine histotripsy from the aspects of the mechanism, animal experiments, clinical trials, advantages, disadvantages, and optimization. KEY CONTENT AND FINDINGS: Histotripsy is a noninvasive, nonionizing, nonthermal ablation technique. The clinical application of histotripsy has made significant progress in the treatment of liver tumors, benign prostatic hyperplasia, and aortic valve calcification stenosis. Phase I clinical trials have demonstrated the safety and efficacy of histotripsy in the treatment of these diseases. More research is needed to evaluate and optimize its efficacy and safety and to fully explore its mechanism of action, pathological and immunological effects, and the short-term and long-term reactions of the body after treatment. CONCLUSIONS: Histotripsy has broad application prospects in ablation therapy and will benefit patients after more clinical trials are conducted in the future.