https://orcid.org/0009-0004-8985-9432
Abstract
Ampullary tumors are uncommon and are frequently associated with hereditary cancer syndromes. Sporadic ampullary adenomas are infrequently reported and may mimic adenocarcinoma clinically and radiographically. We present a 71-year-old male with obstructive jaundice and imaging concerning for malignancy who was found to have a high-grade ampullary adenoma following attempted pancreaticoduodenectomy. Operative management required modification of the standard approach due to intraoperative anatomical distortions. This case highlights the diagnostic challenges in differentiating benign from malignant ampullary lesions and the implications for surgical management.
Introduction
Adenocarcinomas at the Ampulla of Vater represent an uncommon pathology, with a prevalence of ~ 0.2% of all gastrointestinal malignancies [1] and occur with greatest incidence in patients with familial adenomatous polyposis (FAP), Lynch syndrome, and Peutz–Jeghers syndrome [2–4]. Adenomatous changes at this site are particularly common in patients with FAP, with up to 72% of Spiegelman Stage IV patients with FAP having adenomas at the ampulla [2]. The lifetime risk of duodenal/ampullary cancer in patients with FAP is estimated at 3%–5%, and it is one of the leading causes of death in FAP patients who have undergone prophylactic colectomy [5]. Ampullary adenomas are not tracked in Surveillance, Epidemiology, and End Results Program (SEER) data, with sporadic incidence estimated to be between 0.04% and 0.12% of all gastrointestinal malignancies [6]. Sporadic ampullary adenomas in particular have been poorly documented in the literature, with limited reports between 2004 and 2026 [7, 8]. We present the case of a 71-year-old male without FAP who presented with symptoms and initial imaging findings concerning for an adenocarcinoma of the ampulla of Vater. Pathological evaluation of the specimen following resection was significant for a high-grade ampullary adenoma without evidence of adenocarcinoma.
Case presentation
A 71-year-old male with no pertinent past medical history was transferred to our facility from a community hospital, where he presented with poor appetite, 40-pound weight loss, and intermittent confusion over the past several months. He denied a personal or family cancer history and denied alcohol, tobacco, or illicit drug use. Workup revealed elevated total bilirubin of 5.8 mg/dl and elevated alkaline phosphatase, aspartate aminotransferase, and alanine aminotransferase values of 403, 100, and 83 IU/L, respectively. Abdominal ultrasound imaging showed a distended gallbladder with stone burden and intrahepatic and common bile duct (CBD) dilation. Initial workup at our facility demonstrated total bilirubin of 4.9 mg/dl with direct bilirubin of 3.3 mg/dl, and similarly elevated liver function tests (LFTs). Computed tomography (CT) imaging of the head excluded any intracranial abnormalities, and magnetic resonance cholangiopancreatography showed diffuse biliary duct dilation consistent with choledocholithiasis. He subsequently underwent a laparoscopic cholecystectomy with intraoperative cholangiogram that revealed no stones but demonstrated a fungating lesion in the distal CBD, which was accessed via choledochoscopy and biopsied intraoperatively. Two days after this operation, he underwent an endoscopic retrograde cholangiopancreatography (ERCP) for possible CBD stent placement, at which point the origin of the mass at the ampulla was first noted and additional biopsies were taken. His postoperative course was uncomplicated, with LFTs and bilirubin downtrending at the time of discharge 9 days after initial presentation to our hospital.
Approximately 2 weeks post-discharge, this patient was seen for discussion of operative management for his ampullary mass. Prior to discharge, his CA-19-9 was mildly elevated at 61.60 U/ml, decreased to 23.56 U/ml at follow up. Pathological analysis of samples taken during his hospitalization did not show malignancy or high-grade dysplasia of the removed gallbladder and distal CBD mass. Superficial biopsy fragments of the ampullary mass were adenomatous with evidence of high-grade dysplasia, without evidence of invasive malignancy. CT imaging with pancreatic visualization revealed an enhancing periampullary mass measuring approximately 54 × 36 × 36 mm protruding into the transverse duodenal lumen with ampullary obstruction and biliary duct dilation (Figs 1 and 2). The patient subsequently underwent resection of the tumor, which was originally planned as a standard pancreaticoduodenectomy. Attempts to dissect in the retropancreatic plane resulted in severe bleeding from adherent portions of the portal vein to the posterior pancreas, and the mass appeared to involute into the head of the pancreas and extrinsically compress the portal vein, compromising the safety of a standard pancreaticoduodenectomy. An intraoperative change to a transduodenal excision was performed, and the mass was excised completely with removal of the ampulla and portocaval lymphadenectomy. A gastrojejunostomy and feeding tube was placed along with biliary and pancreatic stent placement, with two Jackson-Pratt (JP) drains and a retrograde duodenal stump drain left in place postoperatively. The patient recovered well postoperatively without significant complications. Pathological analysis of the entirety of the mass demonstrated an eroded and ulcerated periampullary and duodenal adenoma with foci of high-grade dysplasia (HGD) with no invasive malignancy identified, though the adenoma extended to the lateral cauterized mucosal edges.
Axial CT imaging of the patient’s abdomen showing a large mass, identified with an arrow, obstructing the common bile duct.
Coronal plane CT imaging of the patient’s abdomen demonstrating a large mass, identified by the arrow, obstructing the common bile duct.
Approximately 1 month post-discharge, his GJ tube was removed, with the 2 JP drains having been removed ~ 2 weeks post-discharge. Since his operation, he has experienced no adverse effects and has returned to normal activity.
Discussion
This case illustrates an uncommon pathological finding of an ampullary mass mimicking ampullary adenocarcinoma in clinical presentation, imaging, and intraoperative appearance. Removal of this mass required a change in approach to a transduodenal resection, which recent retrospective studies have shown to result in significantly lower intraoperative morbidity as well as a 100% 5-year survival rate in cases of adenoma with HGD and carcinoma in-situ (Tis) that were not invasive into the Sphincter of Oddi [9, 10].
Distinguishing ampullary adenoma from adenocarcinoma remains challenging, as the tumor marker CA-19-9 serves as a prognostic and surveillance marker rather than a diagnostic aid, and its role in ampullary adenoma is not well-established [11, 12]. CA-19-9 is often elevated in biliary obstruction, cholangitis, and other non-malignant conditions, making laboratory diagnosis of ampullary adenoma even more challenging [13, 14]. Obstructive symptoms with classic elevations of bilirubin, LFTs, and WBC are also often present in benign as well as malignant tumors. Our patient presented at 71 years of age with decreased appetite, significant weight loss, jaundice, and imaging consistent with biliary obstruction along with elevated LFTs and CA-19-9, findings strongly suggestive for an underlying malignancy. However, he lacked a history of FAP, attenuated FAP, or other hereditary diseases such as Lynch or Peutz–Jeghers syndrome, all of which are known to significantly increase the lifetime risk of development of both ampullary adenocarcinoma and adenoma [1–4].
This patient’s case therefore demonstrates an uncommon case of an ampullary adenoma mimicking adenocarcinoma in the absence of a known hereditary syndrome. Importantly, this case provides additional evidence that transduodenal resection is an effective, well-tolerated operative approach with equivalent survival outcomes to pancreaticoduodenectomy in patients with ampullary adenoma.
Conflicts of interest
None declared.
Funding
None declared.
