Cancer ranks as the second leading cause of death in the U.S., causing as many as 602,350 deaths every year. Due to the ongoing challenges it presents, scientists continue working to find new ways of treating cancer patients.
Among the most novel potential treatments, one new study has found promising results from sound waves, as researchers from the University of Michigan used ultrasound to break up tumors, with surprising success.
Background: How Do Tumors Work?
Cancer is simply unregulated cell growth inside a living body. This growth becomes dangerous for individuals because it can shut down organs and biological pathways, causing pain, damage, and eventually death. This is why it’s important to treat cancers as early as possible with proactive methods like yearly screenings, biopsies, and medication.
To target these growths, doctors and surgeons look for tumors to remove. Tumors, also called neoplasms, are abnormal types of growth in tissues. Tumors form masses that may be externally noticeable or may go undetected for years without proper screening. There are two types of tumors, benign and malignant. Benign tumors are growths that do not transform into cancer. These include things like skin moles. Malignant tumors do transform into cancer and will invade neighboring tissue if not treated. For the researchers at the University of Michigan, these malignant tumors provided an opportunity to test out their new treatment method using sound.
Analysis: Cancer Treatment Using Ultrasound
To see if sound could work as a method of treatment, the researchers developed a special type of ultrasound machine. Ultrasound usually uses sound waves to image inside the body, but for the researchers, they planned to use sound to help destroy the tumors. According to University of Michigan professor Zhen Xu: “Our transducer, designed and built at U-M, delivers high amplitude microsecond-length ultrasound pulses-acoustic cavitation-to focus on the tumor to specifically break it up.”
To test their new device, the scientists used rats with significant tumors. In some cases, their device was able to destroy all of the tumors, but the researchers found something interesting happened when they destroyed only half of the tumor’s mass. When the scientists destroyed 50% to 75% of the tumors, they found that the rat’s immune system attacked the rest of the tumors, destroying them completely. “Even if we don’t target the entire tumor, we can still cause the tumor to regress and also reduce the risk of future metastasis,” explained Xu. This result is especially promising for tumors that cannot be directly targeted in patients, due to location, stage, or size of the tumor.
Outlook: Less Invasive Treatment
The results of this study are promising, not only for showing that the body can heal itself given a stimulus, but also offering a less invasive form of cancer treatment. Because many types of cancer treatments can be invasive, such as surgery, a patient may have unwanted side effects or have to recover from both cancer and a surgical procedure at the same time. A new treatment that uses sound waves is safer and less invasive to a patient, allowing a faster recovery. With cancer being such a leading cause of death, any potential new treatment is welcome, and the researchers hope others will look into ultrasound as a new, powerful treatment option.
Kenna Castleberry is a staff writer at the Debrief and the Science Communicator at JILA (a partnership between the University of Colorado Boulder and NIST). She focuses on deep tech, the metaverse, and quantum technology. You can find more of her work at her website: https://kennacastleberry.com/