Benign neoplasms of the ampulla of Vater are rare. They represent less than 10 percent of periampullary neoplasms, the majority of which are malignant tumors arising from the duodenum, ampulla, or pancreas [1,2]. The most common benign lesions are villous and tubulovillous adenomas; others include hemangiomas, leiomyomas, leiomyofibromas, lipomas, lymphangiomas, and neurogenic tumors [3,4].
Ampullary adenomas can occur sporadically or in the setting of familial polyposis syndromes, such as familial adenomatous polyposis (FAP) and its related conditions. Approximately 40 to 100 percent of patients with FAP who have ampullary adenomas also have coexisting duodenal adenomatous polyps, which are frequently numerous and also have malignant potential [5-9]. (See "Clinical manifestations and diagnosis of familial adenomatous polyposis".)
The prevalence of ampullary adenomas has been estimated to be 0.04 to 0.12 percent in autopsy series [10-12]. However, they are being increasingly recognized premortem with the extensive availability of flexible endoscopy and the widespread application of screening and surveillance programs for high-risk patients, such as those with FAP [5,7,9,13,14].
The treatment of ampullary adenomas will be reviewed here. The clinical manifestations and diagnosis of ampullary adenomas and carcinomas are discussed separately. (See "Clinical manifestations and diagnosis of ampullary adenomas" and "Ampullary carcinoma: Epidemiology, clinical manifestations, diagnosis and staging".)
Although classified as benign, ampullary adenomas have the potential to undergo malignant transformation to ampullary carcinomas. This is thought to occur through an adenoma-to-carcinoma sequence as is seen elsewhere in the gastrointestinal tract [1,10,13,15-21]. As a result, their clinical significance extends beyond the need to treat any associated symptoms.