When the Gleam of Obstruction Isn't Just Stones: A Case Report of Intraductal Papillary Neoplasm of the Bile Duct (IPNB) and the Role of Cholangioscopy in Its Management.

Intraductal papillary neoplasm of the bile duct (IPNB) is a precursor lesion to biliary tract carcinoma. It is characterised by papillary growth within the bile ducts. The diagnosis and management of IPNB are challenging due to its varying presentations and overlapping features with other biliary diseases. We present a case of a 58-year-old male with a history of vomiting, nausea, and upper abdominal discomfort. He also had a history of Gilbert syndrome and hairy cell leukaemia. Imaging studies showed filling defects in the common bile duct (CBD) and a moderate intrahepatic biliary duct prominence. An endoscopic retrograde cholangiopancreatography (ERCP) revealed a soft tissue lesion in the mid-CBD along with significant biliary dilation. Using SpyGlass cholangioscopy, a large polypoid tumour extending from the ampulla was directly visualised, and biopsies confirmed low-grade dysplasia without invasive characteristics. This report highlights the importance of recognising the clinical and radiological features of IPNB and emphasises the role of cholangioscopy in the management of this rare disorder.