Cancer Research: Targeting Rat Tumors Using Sound Waves

According to new studies involving rats, there may be a non-invasive way to permanently destroy cancer cells: the power of sound.

Researchers at the University of Michigan have been able to use only targeted sound waves to degrade rat liver tumors by up to 75% and stimulate the animal’s immune system to attack the remaining cancerous substances. rice field.

This new study important details of is that there was a lasting effect just to destroy the tumor only a small part of. In 80% of the subjects, then the cancer did not have the evidence that was recurrence.

“You can regress tumors and reduce the risk of future metastases without targeting the entire tumor,” said Zhen Xu, a professor of biomedical engineering at the University of Michigan and the corresponding author of the study. Said in a press release.

This treatment, called tissue crushing, uses focused ultrasound to accurately destroy the tissue. It was pioneered by researchers at the University of Michigan, and this relatively new treatment, already tested in different human liver cancer trials in the United States and Europe, could revolutionize cancer treatment. they believe that there is.

“Tissue disruption is a promising option that can overcome the limitations of currently available ablation modalities and provide safe and effective resection of non-invasive liver tumors,” Tejaswi Worlikar, lead author of biomedical engineering, research. PhD students at the release said in the release. “We hope that the knowledge gained from this study will motivate future preclinical and clinical tissue disruption studies towards the ultimate goal of clinical adoption of tissue disruption therapy for patients with liver cancer.”

Often, because of the location or stage of the disease, it is not possible to remove the entire tumor targeting by surgery or existing treatment. Further, since histotripsy is non-invasive therapy, but it may be possible to deal with more tumors possibility that target the entire cancerous substance histotripsy is still logistically impossible is I have. In, in the long term to the success of the treatment, how much of the organization of you will you need to destroy.

This new study was published at the end of March Journal CancersWas the first study focused on whether the partial use of tissue disruption had a lasting effect.

To see if the tumor just bounced, researchers intentionally destroyed only 50-75 percent of rat liver tumors.

Of the treated 11 rats, they observed complete tumor regression in 9 animals, local recurrence of the target tumor tissue in 11 animals all rats until after 12 weeks was observed. By comparison, 100% of the control group of rats of the liver tumor that did not receive the treatment in the same period has experienced a consistent tumor growth.

“The survival outcome of animals treated with tissue disruption was significantly improved compared to controls,” the study said.

Ultrasound is usually used to produce images of what is happening in the body, but in tissue crushing, these sound waves are designed to cause small, controlled cracks in the tissue.

“Our transducers designed and manufactured at UM provide high-amplitude microsecond-length ultrasonic pulses (acoustic cavitation) to focus on the tumor and destroy it,” Xu said. increase. “Traditional ultrasound equipment uses low-amplitude pulses for imaging.”

These pulses create microbubbles inside the tumor that expand and collapse, physically destroying the structure of the tumor and killing cancer cells.

Liver cancer is one of the deadliest cancers in the world, so finding a treatment that has the potential to prevent recurrence is essential, researchers say. According to the Canadian Cancer Society (CCS), liver cancer-related incidence and mortality means that in 2021, an estimated 3,300 Canadians had liver cancer and 1,600 died of liver cancer. increase. Liver cancer survival is one of the lowest, according to CCS data, and only 22% of people with liver cancer are expected to exceed 5 years.

Although Xu’s team has been working on tissue disruption for years, this study is only the latest step towards a viable option for future patients.

An ongoing human experiment for tissue disruption, called # HOPE4LIVER, is sponsored by HistoSonics, a company founded by the University of Michigan. So far, a small number of patients have been successfully treated through trials in the United States and Europe in 2021, and recent patients underwent tissue disruption in the United Kingdom last September. According to the press release from the NHS, it took only 6 minutes 58 seconds, which stood to destroy one of the patient’s tumor.

Patients are being monitored to see if the cancer has recurred — if the study follows the original timeline, it will be completed in 2023.