EUS-FNB guided diagnosis of Neuroendocrine Tumor of Extra-Hepatic Biliary System: A Rare Case Report

Primary neuroendocrine tumors (NETs) of extra-hepatic biliary system are rare. The definitive diagnosis usually relies on immunohistochemistry of post surgical specimen 41 yr gentleman presented with complaints of right hypochondriac dull aching abdominal pain for 1 month. Physical & systemic examination were within normal limits. Liver biochemistry was within normal limits (except mild transaminitis). CECT & MRCP – focal segmental dilatation of biliary radical in segment VI with abrupt cut-off of right posteroinferior bile duct secondary to an ill-defined lesion at the porta-hepatis. Endoscopic ultrasound (EUS)–hypoechoic mass measuring 15 x 15mm involving CHD. EUS guided intraductal FNB was performed using 22G needle. Histology-neuroendocrine tumor WHO Gr 1 with synaptophysin, chromogranin A & CK-19 positivity on immunohistochemistry. DOTA-PET -single well-defined non-metabolically active intraductal vascular arterial phase enhancing lesion involving CHD & extending to right hepatic duct with resultant dilatation of segment VI biliary radicals. Patient underwent surgical resection. Final histopathology-low-grade NET (WHO Gr I) with perineural invasion– pT2aN0M0. Primary NETs of extrahepatic biliary system are rare, & definitive diagnosis can often be established only on surgically resected specimen. This case highlights the use of EUS guided FNB for preoperative diagnosis of this rare condition.

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Artikel online veröffentlicht:
27. März 2025