Contrast-enhanced Intraoperative Ultrasound (CE-IOUS) in Patients with Pancreatic Cancer Undergoing Surgery: Early Outcomes of a Prospective Trial

Abstract

Introduction: Contrast-enhanced intraoperative ultrasound (CE-IOUS) represents an important innovation in hepato-pancreato-biliary imaging. Nonetheless, there is only limited evidence regarding its use during pancreatic surgery. The purpose of the present study was to prospectively assess the potential role of CE-IOUS during pancreatic surgery for the assessment of resectability/staging of the primary tumor, along with identification of potential liver metastases. Method: The protocol of the present study has been registered at clinicaltrials.gov (identifier: NCT04683497). Thirty patients (77% males, mean age 64 years) underwent surgery for pancreatic cancer between November 2020 and July 2021. All patients underwent multidetector Computed Tomography (MDCT), Magnetic Resonance Imaging (MRI), IOUS and CE-IOUS using Sonovue©. Location of the primary tumor, relation to the main vessels, contrast medium uptake modalities, presence of liver metastases, and multifocal pancreatic involvement were evaluated. Results: Twenty-five of the included patients presented pancreatic ductal adenocarcinoma, four patients neuroendocrine tumor, and one patient acinar cell carcinoma (head:24, tail:6). Eight new liver lesions (all metastases) were identified using CE-IOUS in six patients (20%) leading to change of surgical plan (Whipple procedure with resection of segment IV in one patient, Whipple procedure with wedge resection in the second patient, and palliative surgery in four patients). All these new findings were diagnosed after contrast-enhancement; one injection was performed per lesion. Intraoperative findings regarding location and characteristics of primary tumor did not differ from those obtained with preoperative imaging. Conclusions: According to our initial experience, CE-IOUS is a safe and efficient imaging modality with direct impact on operation strategy.