Sporadic ampullary adenoma mimicking adenocarcinoma in the absence of genetic predisposition: a case report.

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.