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Non-ampullary duodenal adenoma
What's new
Updated 2025 AGA guidelines for the management of non-ampullary duodenal adenoma .
Background
Overview
Definition
Non-ampullary duodenal adenomas are benign epithelial tumors arising from the duodenal mucosa outside the ampulla of Vater. These tumors have the potential to progress to duodenal adenocarcinoma, particularly in patients with underlying genetic conditions, such as familial adenomatous polyposis.
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Pathophysiology
The exact pathophysiology is not fully understood, but the WNT signaling pathway is known to play a significant role in the initiation of these adenomas, with a high prevalence of diffuse or focal nuclear β-catenin accumulation. Non-ampullary duodenal adenomas frequently exhibit mutations in genes such as APC, KRAS, and GNAS.
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Epidemiology
Non-ampullary duodenal polyps are found in up to 5% of all upper gastrointestinal endoscopies, most of which are identified incidentally in asymptomatic patients, with duodenal adenomas accounting for 10-20% of these lesions. The incidence of non-ampullary duodenal adenomas in Japan is estimated at 2.4 per 100,000 person-years.
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Risk factors
Non-ampullary duodenal adenomas can develop sporadically or in association with a familial syndrome, such as familial adenomatous polyposis or MUTYH-associated polyposis.
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Disease course
Clinically, most non-ampullary duodenal adenomas are asymptomatic and are often discovered incidentally, though they may present with gastrointestinal bleeding or mimic other conditions such as peptic ulcer disease.
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Prognosis and risk of recurrence
The prognosis of non-ampullary duodenal adenomas is generally good due to their benign nature; however, there is a risk of progression to invasive carcinoma, especially in patients with familial adenomatous polyposis.
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Guidelines
Key sources
The following summarized guidelines for the evaluation and management of non-ampullary duodenal adenoma are prepared by our editorial team based on guidelines from the American Gastroenterological Association (AGA 2025), the American Society of Colon and Rectal Surgeons (ASCRS 2024), the European Society of Gastrointestinal Endoscopy (ESGE 2021), the American Society for Gastrointestinal Endoscopy (ASGE 2020,2015), and the American College of ...
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Diagnostic procedures
Technical considerations for endoscopy: as per AGA 2025 guidelines, identify the major and minor papillae and obtain photodocumentation during duodenal endoscopic inspection to ensure no involvement by the lesion. Consider adding a clear distal attachment device to a forward-viewing gastroscope to improve visualization of the papilla and the medial wall. Use a side-viewing duodenoscope when the major and minor papilla are not visible with the gastroscope and for most lesions on the medial wall of the duodenum within 5 cm of the ampulla.
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Colonic and small bowel evaluation
Biopsy
Therapeutic procedures
Endoscopic resection: as per AGA 2025 guidelines, do not perform endoscopic resection for nondysplastic lesions unless they are symptomatic or bleeding.
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Endoscopic ablation
Specific circumstances
Patients with familial adenomatous polyposis, screening: as per ASCRS 2024 guidelines, obtain screening for duodenal adenomas in patients with familial adenomatous polyposis with a baseline upper gastrointestinal endoscopy starting at the age of 20-25 years and subsequent examinations at intervals based on endoscopic findings.
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Patients with familial adenomatous polyposis (endoscopic resection)
Follow-up and surveillance
Endoscopic surveillance: as per AGA 2025 guidelines, obtain initial endoscopic surveillance for a completely resected duodenal adenoma at an interval of 6 months. Recognize that although recurrence is often diminutive, it is frequently scarred and not amenable to conventional snare resection, potentially requiring avulsion techniques to achieve a cure.
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Management of recurrent disease