525 Ampullary Adenoma Associated with Familial Adenomatous Polyposis. An Uncommon Cause of Pancreatitis Diagnosed on Transcystic Choledochoscopy

We present the case of a gentleman in his forties, who presented with post-prandial right upper quadrant pain associated with nausea and vomiting. His background was notable for a total colectomy and end ileostomy at the age of 33 in the setting of Familial Adematous Polyposis. His past medical history was notable for depression and anxiety. On examination he was haemodynamically stable and afebrile, with percussion tenderness and localised guarding in the right upper quadrant. Investigations revealed an elevated lipase of 4700. His liver function tests were notable for a bilirubin of 50, and mild cholestatic derangement on his liver function tests. Diagnosis of mild pancreatitis was established. Ultrasound demonstrated sludge in the gallbladder, though no evidence of common bile duct dilatation. An MRCP (Figure 1) was first performed, which demonstrated interstitial pancreatitis, associated with a distal common bile duct filling defect favoured to be sludge. Laparoscopic choelcystectomy with transcystic bile duct exploration was performed utilising a flexible choledodoscope. Multiple polyploid lesions were noted arising from the distal common bile duct, extending to the Ampulla (Video 1, Figure 2). A biopsy was not obtained. A Fanelli biliary stent was deployed via a trancystic approach to allow for biliary drainage. An ERCP was subsequently performed confirming the diagnosis of ampullary adenoma. Long term follows up studies would suggest the risk of malignant transformation is low, thus while there is no standardised approach to ampullary adenoma, endoscopic resection is preferred to surgical resection and pancreaticoduodenectomy, accepting a high likelihood of recurrence.