Endoscopic Ultrasound for Nodal Staging in Patients with Resectable Cholangiocarcinoma

<b>Background</b>: Lymph node (LN) involvement is a negative prognostic factor for patients with cholangiocarcinoma (CCA). Preoperative assessment of the LN could potentially aid therapy decision making. Endoscopic ultrasound (EUS) can be used to sample suspicious LN. The aim of this study was to evaluate the clinical impact of EUS for suspicious LN in patients with presumed resectable CCA. <b>Methods</b>: In this single-center cohort study, patients with potentially resectable CCA who underwent preoperative linear EUS between 2019 and 2024 were retrospectively included. The primary aims were the percentage of malignant LN detected and the clinical impact of EUS, which was defined as the percentage of patients who were precluded from surgical exploration due to pathologically confirmed LN metastases found with EUS tissue acquisition (EUS-TA). The secondary aim was the complication rate of EUS-TA. <b>Results</b>: A total of 135 patients were included, of whom 12 (8.9%) had intrahepatic CCA (iCCA), 65 (48.1%) had perihilar CCA (pCCA), 13 had (9.6%) middle bile duct CCA (mCCA), and 45 (33.3%) had distal CCA (dCCA). Across 148 EUS procedures, 139 LNs were identified, and EUS-TA was performed on 63 LNs among 55 patients. LN metastases were detected by EUS-TA for iCCA, pCCA, mCCA, and dCCA, in 25%, 6.2%, 15.4%, and 4.4%, respectively. EUS and EUS-TA influenced surgical work-up for iCCA, pCCA, mCCA, and dCCA in 25%, 1.5%, 15.4%, and 0.0%, respectively. No complications associated with EUS were noted. <b>Conclusions</b>: Preoperative EUS for nodal staging had an important clinical impact in patients with presumed resectable iCCA and mCCA, but less for pCCA and dCCA. Further prospective studies should investigate whether systematic nodal staging with EUS could improve preoperative decision making even further.