Natural history of ampullary adenoma in familial adenomatous polyposis: reconfirmation of benign nature during extended surveillance.

Surgical or endoscopic papillectomy may be one of the therapeutic strategies for patients with familial adenomatous polyposis (FAP). To determine whether prophylactic papillectomy is necessary for FAP, we investigated the natural history of the ampullary adenoma in FAP. Eighteen subjects with FAP were surveyed by duodenoscopy with biopsy for >10 yr. Endoscopic appearance, histological findings, and immunohistochemical stainings for Ki-67 of ampulla were compared between initial and final endoscopic examinations. The endoscopic grade in the ampulla remained unchanged in 16 subjects, whereas in two subjects an increase in the endoscopic grade was noted. In two subjects adenoma developed from an endoscopically and histologically normal ampulla. The histological grade of dysplasia increased in three of 12 subjects who initially had adenoma. The labeling index for Ki-67 was not different between initial and final examinations. These data suggest that most ampullary adenoma of patients with FAP is static and that aggressive endoscopic or surgical removal is unnecessary for the adenoma.