A case of duodenal adenocarcinoma masquerading as acute cholecystitis and biliary pancreatitis

Background: Small intestinal tumors are rare accounting for less than 5% of all gastrointestinal (GI) tumors. Primary duodenal carcinoma is very rare among GI tumors and usually presents with non-specific signs and symptoms rendering it difficult for early diagnosis. Importance of early diagnosis arises from the fact that the only curative treatment is radical surgical resection before metastasis. Whipple’s procedure remains the most accepted surgical intervention for resectable tumors. Case presentation: An 82-year-old female presented to the emergency department with a one-day history of epigastric pain and nausea without vomiting. Abdominal examination revealed tenderness in the epigastrium and right upper quadrant. Abdominal ultrasound and laboratory tests were consistent with acute cholecystitis and biliary pancreatitis. She underwent laparoscopic cholecystectomy and intra operative cholangiogram which revealed a dilated common bile duct with questionable cholelithiasis. Post-operative computed tomography (CT) scan revealed duodenal thickening at the periampullary region suggesting a mass without evidence of metastasis. Esophagogastroduodenoscopy (EGD) confirmed a periampullary mass. Histopathological examination of biopsied tissue revealed moderately differentiated adenocarcinoma. The patient underwent pancreaticoduodenectomy (Whipple’s procedure) and had a long, complicated post-operative course and eventually died. Conclusions: Duodenal adenocarcinoma (DAC) is rare and may present with concomitant acute cholecystitis and biliary pancreatitis.