The Utility of Endosonographic Evaluation of the Liver Despite a Normal Pre-Procedural Imaging Study for Patients Undergoing EUS for Pancreatic Masses

Abstract

Introduction: Endoscopic ultrasound (EUS) and fine needle aspiration (FNA) has increasingly become the diagnostic test of choice to evaluate pancreatic masses detected on imaging studies. The utility of routine EUS examination of the left lobe of the liver, despite a negative pre-procedural CT or MRI, for potential metastatic disease has not been evaluated. The objective of the current study was to determine if EUS of the left lobe of the liver would detect lesions that were not visible on pre-procedural imaging modalities of either CT or MRI and the impact of FNA from these lesions. Methods: Cases of EUS for pancreatic masses performed at a single academic tertiary care center from January of 2010 to October of 2017 were retrospectively reviewed (n = 774 ). All EUS were performed by faculty with formal advanced fellowship training and more than 10 years of EUS experience. Those cases where EUS - FNA of the liver was performed were analyzed. Patient's gender, age, race, rapid onsite evaluation (ROSE) result, EUS characteristics, and final liver pathological diagnosis were analyzed. All FNA specimens underwent (ROSE) with cytopathologist guidance. Results: A total of 774 EUS cases performed for pancreatic masses were reviewed of which 35 cases had EUS-FNA of a liver lesion. 10 cases of EUS- FNA had a negative pre-procedural imaging study (Either CT or MRI). The 10 patients had a mean age of 71 year with 3 males and 7 females. 9 of them were Caucasian and 1 was Hispanic. The EUS showed a total of 13 lesions with endosonographic characteristics of hypoechoic lesions in 8 cases, mixed hypoechoic-isoechoic lesions in 2 cases, poorly demarcated border in 5 cases, round well demarcated in 5 cases, with a mean size of 10.20 mm. FNA using a 25-gauge needle with ROSE of the liver lesions yielded 9 cases of metastatic pancreatic adenocarcinoma. The other case was a benign lesion. In 7 cases the number of needle passes was 2, while in the remaining 3 cases, 2 of them needed 3 passes, and in one case a single pass was required. Conclusion: In these 9 cases of metastatic pancreatic adenocarcinoma, the discovery of metastatic liver disease resulted in upstaging of the diagnosis and altered the course of management. Conclusion: Routine evaluation of the left lobe of the liver despite negative pre-procedural imaging may be warranted in patients presenting for EUS of pancreatic masses.