High prevalence of adenomas and microadenomas of the duodenal papilla and periampullary region in patients with familial adenomatous polyposis.

Abstract

Patients with familial adenomatous polyposis (FAP) are traditionally considered to be at high risk for duodenal-papillary and periampullary adenomas and cancer. To evaluate prospectively the prevalence, histology and clinical significance of ampullary and periampullary macroscopic and microscopic lesions in our population of affected patients. Three gastroenterological departments of northern Italian hospitals. Twenty-five affected patients were carefully investigated over a 24-month period by end-viewing and side-viewing upper panendoscopy. Biopsies were performed on representative macroscopic lesions and randomly on normal-appearing papillary and periampullary mucosa. Seven patients had macroscopic adenomas of the duodenal papilla, three of the periampullary region and five at both sites (cumulative prevalence 40%). An additional six patients had macroadenomas in the rest of the duodenum (overall prevalence 64%). Microscopic adenomas were identified in nine and two patients in the papilla and periampullary region, respectively, and in three at both sites (overall prevalence 44%). Thus, a total of 17 (68%) patients presented macro- or microadenomas at these locations. The prevalence rose to 72%, when a further patient with macroadenomas in the rest of the duodenum only was included. Malignancy was not encountered and severe dysplasia was observed only in a macroadenoma of the second duodenal portion. A higher frequency of macroadenomas in the papilla and periampullary region was significantly correlated with the presence and number of such lesions in the rest of the duodenum (P = 0.04). No other significant association was detected either between micro- or macroadenomas at different sites or with the demographic, clinical and pathological features. This study confirms that the duodenal papilla and periampullary region are sites with high prevalence of macro- and microscopic adenomas in patients with FAP. However, our data do not seem to support a higher frequency and malignancy potential of such lesions as compared to polyps in the rest of the duodenum. Nevertheless, these findings warrant a periodic, careful examination of the duodenum with either end-viewing or side-viewing endoscopy, the need for random biopsies of the papilla and periampullary region and the removal of any larger or rapidly growing lesions detected.