Liver histotripsy reaches 972 U.S. patients, study finds

A billing code opened a window onto 972 liver histotripsy patients treated in U.S. clinical practice. At the University of Virginia, a team led by Allan Tsung, professor and chair of surgery, used de-identified electronic health records to track who received the procedure and what happened in the short term.

The treatment arrived in routine care nearly three years after the Food and Drug Administration cleared the HistoSonics Edison histotripsy system for primary and metastatic liver tumors. In this national cohort, 69.8% of patients had cancer that had spread to the liver, while 30.2% had primary liver malignancies. Colorectal and pancreatic cancers were the most common primary tumors among metastatic cases; hepatocellular carcinoma and intrahepatic cholangiocarcinoma led among primary liver cancers.

The procedure often fit into a single visit. 88.2% of patients were treated in urban centers as outpatients and discharged the same day. Thirty-day readmissions and emergency visits were both below 1%, and the researchers described toxicity as low.

The harder number is 11.1% mortality within 30 days, representing 108 patients. Tsung’s team says the figure raises the possibility that some patients received histotripsy close to death, as end-of-life care, rather than solely for local disease control.

So what changes for patients and clinicians? Histotripsy is already being used beyond small specialist series, including in people with aggressive metastatic cancers. That makes patient selection the immediate practical question: surgeons, medical oncologists, interventional radiologists and hepatologists need stronger comparative evidence to judge who is likely to gain cancer control or survival benefit. The University of Virginia researchers say prospective outcomes and comparative studies are still required.