10/27/2019 Ryann Monahan, ECE ILLINOIS
Written by Ryann Monahan, ECE ILLINOIS
A new grant from the National Cancer Institute is bringing ECE ILLINOIS researchers closer to discovering new methods to diagnose liver cancer. The team’s innovative techniques will help diagnose without the need for contrast agents.
ECE ILLINOIS Research Assistant Professor Aiguo Han and Research Professor William D O'Brien, Jr., Donald Biggar Willett Professor Emeritus in Electrical and Computer Engineering, both with the Bioacoustics Research Laboratory, have received the $2.4 million five-year grant to investigate new quantitative ultrasound (QUS) methodology to diagnose liver cancer (specifically, hepatocellular carcinoma, or HCC) that does not require the use of contrast agents.
HCC is the most common primary malignancy of the liver (accounting for 85%-90% of all primary liver cancers), with over half a million new cases diagnosed annually. Up to 90% of cases of HCC occur in patients with cirrhosis, a condition characterized by disruption of hepatic architecture with regenerative nodules surrounded by fibrous septa.
Current guidelines recommend that cirrhotic patients undergo HCC screening every 6 months using conventional ultrasound without contrast agents. The application of ultrasound screening has resulted in the discovery of an increasing number of small cirrhotic-liver nodules (< 2 cm).
“However, conventional ultrasound without contrast agents has low sensitivity (~60%) to detect HCCs. There is significant clinical value to develop a more accurate HCC screening method, as well as to characterize/classify small nodules to provide information for medical decision making with regard to disease management,” Han said.
Currently, dynamic imaging (e.g., contrast-enhanced ultrasound, or CEUS) is widely used to characterize liver nodules. The arterial vascularization in HCC produces a characteristic radiologic pattern that allows for a reliable malignancy diagnosis on dynamic imaging for tumors > 3 cm.
“Unfortunately, dynamic imaging is often not useful for malignancy diagnosis in small nodules (< 2 cm) because hyperarterialization is incomplete or absent. Furthermore, CEUS is invasive, requiring intravenous contrast agent administration for which multiple lesions need to be examined with separate contrast agent injections. Therefore, CEUS is not appropriate for HCC screening/surveillance in cirrhotic patients,” O’Brien explained.
Han and O’Brien’s team has proposed to develop new quantitative ultrasound (QUS) methods for liver nodule characterization and HCC screening/diagnosis without using contrast agents. “QUS is an ultrasound technology that extracts quantitative information about tissue microstructure from ultrasound echo signals, in contrast with conventional ultrasound where qualitative information is displayed. A component of the ultrasound backscattered signal, quantified by the QUS structure function parameter, is sensitive to the architectural pattern of tissue microstructure (e.g., liver cell nuclei),” Han said.
“It is known that the hepatic architecture changes as the disease progresses from regenerative nodules to HCCs. Therefore, our team proposed that QUS structure function could serve to differentiate liver nodules based on the architectural pattern,” O’Brien emphasized.
The goal of the team’s research is to systematically study the QUS structure function parameter using animal solid tumors, human liver, and HCC data to demonstrate that the structure function is sufficiently sensitive to the disruption of hepatic architecture and vasculature due to cirrhosis and particularly HCC in order to diagnose HCC without the need for contrast agents.
The UIUC’s Bioacoustics Research Laboratory faculty members including Han and O’Brien will collaborate locally with biostatistician Prof. Doug Simpson and board-certified veterinary pathologist Prof. Matt Wallig and in San Diego with physicists and clinicians (radiologists, hepatologists, pathologists) at the Moores NCI-designated Comprehensive Cancer Center at the University of California - San Diego.