Post written by Kosuke Minaga, MD, PhD, and Masayuki Kitano, MD, PhD, from the Department of Gastroenterology and Hepatology, Kindai University Faculty of Medicine, Osaka-Sayama, and the Second Department of Internal Medicine, Wakayama Medical University School of Medicine, Wakayama, Japan.

The focus of this study was to assess the usefulness of Kupffer-phase imaging in contrast-enhanced harmonic EUS (CH-EUS) for diagnosing liver metastases from pancreatic cancer.  

Early detection of liver metastases in patients with pancreatic cancer is important for clinical decision making and crucial to the prognosis for survival. Although contrast-enhanced CT (CE-CT) has been widely used as a standard imaging modality to determine the stage of pancreatic cancer, it cannot detect liver metastases smaller than 1 cm efficiently. Recent studies showed fundamental B-mode EUS (FB-EUS) could detect liver metastases that are undetectable with conventional imaging modalities; however, the ability of FB-EUS to characterize liver lesions, especially small ones, is still limited. Since no report has focused on liver assessment with Kupffer-phase imaging in CH-EUS, we conducted a study to compare the diagnostic ability of CH-EUS against that of CE-CT and FB-EUS for liver metastases in the left liver lobe.

We studied 426 pancreatic cancer patients. The diagnostic accuracy of CE-CT, FB-EUS, and CH-EUS was 90.6%, 93.4%, and 98.4%, respectively. The sensitivity and diagnostic accuracy of CH-EUS for metastasis in the left liver lobe were significantly higher than those of FB-EUS or CE-CT. The sensitivity of CH-EUS for detecting small liver metastasis (<1 cm) was considerably higher than that of CE-CT or FB-EUS (P<.001). In 2.1%, a small but nonnegligible number of patients, only CH-EUS could detect a single distant metastasis of the left liver lobe, thereby upgrading the tumor staging and altering the clinical management. Our study showed Kupffer-phase imaging in CH-EUS for liver observation following a routine evaluation of pancreatic tumor was more sensitive and accurate in detecting left-lobe liver metastases, particularly small lesions. Moreover, considering that CH-EUS is less invasive and cost-effective with almost no contraindications, CH-EUS-based Kupffer-phase imaging could be a useful and reliable imaging modality worth performing before making treatment decisions in patients with pancreatic cancer.

Figure 2. Typical image of liver metastasis in the left lobe of the liver (A, fundamental B-mode EUS; B, Kupffer-phase image in contrast-enhanced harmonic EUS). Liver metastasis is visualized as a perfusion defect on the Kupffer-phase image in contrast-enhanced harmonic EUS (CH-EUS). The right image shows the Kupffer-phase image in CH-EUS, and the left image shows a fundamental B-mode monitor image in real time linked to the right image. In the Kupffer-phase image, a small liver metastasis is clearly depicted as a perfusion defect (arrowheads).

Read the full article online.

The information presented in Endoscopedia reflects the opinions of the authors and does not represent the position of the American Society for Gastrointestinal Endoscopy (ASGE). ASGE expressly disclaims any warranties or guarantees, expressed or implied, and is not liable for damages of any kind in connection with the material, information, or procedures set forth.