Non-Invasive Sound Technology That Breaks Down Tumors, Kills Cancer Cells, Stimulates Immune System

700kHz, 260-element Histopathology Ultrasound Array Transducer

The sound partially destroys the tumor and will not return

A new technique pioneered in rats at the University of Michigan could improve outcomes in cancer and neurological diseases

A non-invasive sound technology developed at the University of Michigan can break down liver tumors in rats, kill cancer cells, and stimulate the immune system to prevent further spread -- an advance that could improve outcomes in human cancers

By destroying only 50 to 75 percent of the liver tumor volume, the rats' immune systems were able to clear the rest, and more than 80 percent of the animals showed no signs of recurrence or metastasis

"Even if we don't target the entire tumor, we can still regress the tumor and reduce the risk of future metastasis," said Zhen Xu, a professor of biomedical engineering at the University of Michigan and corresponding author of the Cancer study

Zhen Xu, a professor of biomedical engineering at the University of Michigan, works in her office

The results also suggest that the treatment stimulated an immune response in the rats that may help eventually return to non-targeted parts of the tumor and prevent the cancer from spreading further

The treatment, called tissue puncture, is a non-invasive focused ultrasound that mechanically destroys the target tissue with millimeter precision

In many clinical situations, it is not possible to directly target the entire tumor due to factors such as the size, location, or stage of the mass

Tejaswi Worlikar, PhD student in biomedical engineering, said: "Tissue biopsy is a promising option to overcome the limitations of currently available ablation modalities and provide safe and effective non-invasive ablation of liver tumors

Liver cancer is one of the top ten causes of cancer-related death globally and in the United States

A typical ultrasound uses sound waves to create images of the inside of the body, and engineers at the University of Michigan have pioneered the use of these sound waves for treatment

"Our transducer, designed and fabricated at UM, delivers high-amplitude microsecond-long ultrasound pulses -- acoustic cavitation -- focused on the tumor to break it down," Xu said

Microsecond pulses from the sensor create microbubbles in the target tissue, which rapidly expand and collapse

Reference: "Impact of Histotripsy on Development of Intrahepatic Metastases in a Rodent Liver Tumor Model" by Tejaswi Worlikar, Man Zhang, Anutosh Ganguly, Timothy L.