Impact of Endoscopic Ultrasound in Unresectable Perihilar Cholangiocarcinoma patients in Liver Transplantation work-up.

BACKGROUND AND STUDY AIMS: For a highly selected group of patients with unresectable perihilar cholangiocarcinoma (pCCA) liver transplantation (LT) is a treatment option. The Dutch screening protocol comprises non-regional lymph node (LN) assessment by endoscopic ultrasound (EUS) and whenever LN metastases are identified, further LT screening is precluded. The aim of this study is to investigate the yield of EUS in patients with pCCA who are potentially eligible for LT.

METHODS: In this retrospective, nationwide cohort study, all consecutive patients with suspected unresectable pCCA who underwent EUS in the screening protocol for LT were included from 2011-2021. During EUS, sampling of a 'suspicious' non-regional LN was performed based on the endoscopists discretion. The primary outcome was the added value of EUS, defined as number of patients who were precluded from further screening due to malignant LN.

RESULTS: A total of 75 patients was included in whom 84 EUS procedures were performed, with EUS guided tissue acquisition confirming malignancy in LN in 3/75 (4%) patients. In the 43 who underwent surgical staging conform the protocol, non-regional LN were identified in 6 (14%) patients. Regional LN were found in 7 patients in post-LT resected specimens.

CONCLUSIONS: Our current EUS screening for the detection of malignant LN in patients with pCCA eligible for LT shows a limited but clinically important yield. EUS with systematic screening of all LN stations, both regional and non-regional and sampling of 'suspicious' lymph nodes according to defined and set criteria could potentially increase this yield.