Carcinoma in adenoma of the minor duodenal papilla completely resected by endoscopic mucosal resection.

Adenocarcinoma of the minor duodenal papilla is rare, and most previously reported cases have been treated by pancreaticoduodenectomy. An 82-year-old woman underwent endoscopy for anemia, which revealed a granular, flat-elevated lesion in the descending duodenum, 2 cm proximal to the major papilla. Endoscopic retrograde pancreatography showed leakage of contrast medium from the orifice of the accessory pancreatic duct at the lesion, confirming a tumor of the minor papilla. The initial biopsy showed adenoma, and the lesion was followed. Six months later it had enlarged and become friable, and repeat biopsy was suspicious for adenocarcinoma. Because pancreaticoduodenectomy was considered too invasive given her age and comorbidities, and because the minor papilla-unlike the major papilla-can be lifted by submucosal injection, en-bloc endoscopic mucosal resection was performed for both diagnostic and therapeutic purposes. Histology showed well-differentiated adenocarcinoma arising in adenoma, confined to the mucosa, with tumor-free margins and no lymphovascular invasion. No adverse events occurred, and no recurrence was observed during approximately 5 years of follow-up (endoscopic surveillance up to 2 years); the patient later died of an unrelated cause. Endoscopic mucosal resection may be a minimally invasive option achieving histologically complete resection in selected intramucosal carcinomas of the minor duodenal papilla.