Beyond the supposed choledochocele, a hidden ampullary carcinoma

A 38-year-old woman was referred to our endoscopy unit at day 10 after delivery. During the 7th month of pregnancy, she underwent a laparoscopic cholecystectomy. Laboratory tests before endoscopic retrograde cholangiopancreatography were within normal range. Endoscopy demonstrates an ampullary bulging soft and fluctuant when probed with the papillotome evocating a type III choledochal cyst of at least 3 cm size (Panel A). The papilla could not be seen even when the bulging was passed making the biliary cannulation impossible. The cholangiography performed, by the transcystic route showed a dilated common bile duct with an intraduodenal cystic dilation without biliary stone or evidence of ampullary mass (Panel B). A needle knife fistulotomy leading to an unexpected abundant pus flow was performed (Panel C). The cystic dilation decreased progressively revealing an ulcerative ampulla type with a nodular base (Panel D) and irregular margins evocating an ampullary malignancy (Panel E). A double pigtail biliary stent was placed (Panel F). Biopsies revealed adenocarcinoma.