The #HOPE4LIVER single-arm Pivotal Trial for Histotripsy of Primary and Metastatic Liver Tumors: 1-year Update of Clinical Outcomes.

Objective: To evaluate the 1-year clinical outcomes of patients enrolled in the #HOPE4LIVER trial of hepatic histotripsy.

Summary background data: Histotripsy is a novel non-invasive, non-thermal focused ultrasound therapy that liquefies tissue at the focal point of the transducer. Following diagnostic ultrasound targeting, an automated treatment is performed via a robotic arm to treat a user-defined volume of tissue.

Methods: Forty-seven patients were enrolled at 14 sites in the United States and Europe. Included patients were ineligible for or had opted out of standard therapies. Tumor control was evaluated via a core laboratory with a primary assessment at each time point and a post hoc assessment performed following completion of each time point to allow for a learning curve of interpreting imaging findings of this novel therapy. Overall survival and freedom from local tumor progression were evaluated via the Kaplan-Meier method.

Results: Nineteen patients with hepatocellular carcinoma and 28 with metastatic disease were enrolled, of whom 89.5% (17/19) and 96.4% (27/28) had multifocal hepatic tumors at the time of treatment. Fifty-two tumors were treated. The 1-year local control rate was 63.4% using the primary assessment method and 90% using the post hoc method. There were six serious adverse device-related effects within 30 days of treatment. Only one non-serious adverse device-related effect was observed after 30 days of treatment. Overall survival at 1-year was 73.3% for patients with HCC and 48.6% for patients with metastatic disease.

Conclusions: Histotripsy results in local control of liver tumors at 1-year that is consistent with current locoregional therapies. The safety profile is favorable, and survival at 1 year is comparable with other therapies for similar disease stages.