NIBIB awards Dahl & Willmann Labs R21 for Molecular Imaging of Pancreatic Cancer

Dr. Jeremy Dahl and Dr. Juergen Willmann

The National Institute of Biomedical Imaging and Bioengineering (NIBIB) has awarded a R21 grant entitled "High Sensitivity Molecular Ultrasound Imaging in Pancreatic Cancer" to the Dahl and Willmann labs.

Pancreatic ductal adenocarcinoma (PDAC) is a very lethal form of cancer. Due to a lack of noticeable clinical symptoms, most patients already have advanced disease at the time of diagnosis; patients who have PDAC detected at an early stage may undergo curative resection and have much better chance of survival overall. Better methods to detect PDAC at early stages are thus critical to improve the treatment and prognosis for patients with PDAC. However, there is currently a lack of both sensitive and specific imaging tests to detect PDAC--a problem that is compounded by the small size of the tumor foci at early stages.

In a joint effort with the Juergen Willmann lab, we are developing a highly specific and sensitive ultrasound imaging technique to detect early stage PDAC. Our colleagues in the Willmann lab have identified and validated a new biomarker that is differentially expressed in human PDAC (but only minimally present in normal pancreas or chronic pancreatitis); microbubbles targeted to this biomarker are being developed to enable molecular ultrasound imaging. Our lab is developing a highly-sensitive molecular ultrasound imaging technique based on the Short-Lag Spatial Coherence (SLSC) beamformer to improve the detection of very low concentrations of targeted microbubbles. This highly specific and sensitive imaging technique may aid clinicians in early-stage detection of PDAC and allow life-saving intervention.

In vivo contrast-enhanced ultrasound (CEUS) images of two mouse tumors are presented above, showing the conventional CEUS and SLSC-CEUS techniques. A high amplitude pulse is used to burst and destroy the microbubbles (MBs, visible in the pre-burst images). By taking the difference between the pre-burst and post-burst images, the tissue signals are removed while retaining MB signals. SLSC-CEUS shows a higher sensitivity to MBs in tumors with high (left) and low (right) MB retention.