ROGER EXPLORES… Ultrasound

by Roger Wilson

Recently, I stumbled over a press release from Cambridge Hospitals about High Intensity Focused Ultrasound.  I had been coming across the topic  already several times and became curious:  what is it, what is it good for?   I decided to dig deeper – here is what I discovered.

High Intensity focused ultrasound (HIFU) delivers energy to a specific point inside the body, notably solid cancers. HIFU works by heating tissue to destroy it. This ablative approach is used already by other technologies and has proven value in sarcoma so I was keen to see whether HIFU offers benefits to sarcoma patients. HIFU seems also to stimulate the body’s immune system and some secondary anti-cancer activity has been seen. Several clinical studies have taken place and regulatory criteria have been met for very specific anti-cancer use, an important one is prostate cancer with another being bone metastasis. The technology is being further developed to explore its potential.

There is a clinical study, SarcAblate, designed in Oxford to generate evidence regarding safety and feasibility of HIFU for ablation of soft tissue sarcomas and intra-abdominal desmoids. The aim is to generate data about the efficacy of HIFU against these tumour types which can help in the design of later phase studies. Short-term outcomes include feasibility, safety and the completeness of destruction of the tumour. Long-term outcomes include one-year survival, local recurrence and quality of life metrics (including pain scores). The study will also look at the immunological response following ablation of soft tissue sarcoma (STS) using both blood and tumour samples. It is hoped to have early results within two years.

Histotripsy is a specific technique within HIFU. It uses the focussed ultra-sound waves to create microscopic bubbles in the cancer tumour, rather than heat, and the bubbles mechanically make cavities which break up the cancer tissue. Instead of relying on heat, it uses short, pulsed ultrasound waves to create the tiny bubbles.  The developers claim that this mechanical, rather than thermal, effect allows it to precisely ablate tissue without causing heat damage to surrounding areas. The liquefied tumour tissue passes out of the patient’s system just like any other liquid.

Histotripsy was approved by the US Food and Drug Administration for the treatment of liver tumours in October 2023. The following year, a small study funded by the company commercialising the technology, found that the approach achieved technical success against 95% of liver tumours. Histotripsy may have side effects ranging from abdominal pain to internal bleeding, but complications seem to be rare and the method is generally seen as safe.

In June 2025, the UK became the first European country to approve histotripsy for routine clinical use as one of eight innovative medical devices selected to address unmet clinical need.[i] The treatment of liver cancer is usually surgery plus adjuvant radiotherapy and chemotherapy. By using a non-invasive and targeted approach, the regulators found that histotripsy makes treatment quicker and safer, all done in one treatment and the patient able to return home soon afterwards.

Cambridge University hospital became the first user of the technology in the UK and treated its first routine clinical patient in October 2025.

This is a technology which is making steps forward and for which I want to see more trials in sarcoma. Other ablative therapies using radiation, lasers, and radiofrequencies are now widely used to treat more advanced sarcoma. The introduction of ultrasound as an adjunct or alternative to surgery looks as though it may be a valuable new treatment approach.

Watch this space.

[i] Under the Innovative Devices Access Pathway (pilot phase) oft he Medicines and Healthcare Products Regulator Agency (MHRA).

 

Credits:  Graphic design by Karl Berger