Adenoma of the papillae of Vater. Report of eleven cases

Ampullary adenoma: clinical manifestations, diagnosis, and treatment

Ampullary adenomas occur sporadically and in the setting of familial polyposis syndromes. In either case, and whether symptomatic at presentation or found asymptomatically in the setting of endoscopic screening programs, they are premalignant lesions with risk for malignant degeneration to carcinoma following the adenoma-to-carcinoma sequence that is well recognized in colonic adenocarcinoma. Accordingly, many experts advocate excision, although others cite the low rate of histologic progression suggested by some recent studies as justification for close endoscopic surveillance rather than excision before demonstration of dysplastic change. This recommendation, however, is complicated by considerable data underscoring the limited accuracy of endoscopic forceps biopsy in detecting occult foci of carcinoma within ampullary adenoma. Thus, the optimal management of these lesions continues to generate considerable controversy. Indications for excision of an ampullary adenoma include treatment of immediate symptoms as well as prevention of malignant degeneration. Although pancreaticoduodenectomy has long been considered the standard procedure for ampullary carcinoma, much controversy exists regarding the procedure of choice for ampullary adenoma. Radical surgery (pancreaticoduodenectomy) possesses the advantage of low recurrence rate but at the expense of higher morbidity (25%-65%) and mortality (0%-10%). Local surgical excision (surgical ampullectomy) possesses the advantages of lower morbidity (0%-25%), essentially nil mortality, and possibly decreased length of hospital stay, but decidedly higher recurrence rates (generally 5%-30%) and the need for postoperative endoscopic surveillance. Snare ampullectomy is a newer endoscopic excisional technique for which limited data are available; advantages compared with radical surgery mirror those of local surgical excision, with apparent lower mortality (0%-1%) and lower morbidity (12%). Presumed advantages compared with local surgical excision include lack of necessity for general anesthesia and laparotomy with comparable morbidity. Disadvantages seem to include limited availability of experienced operators, procedural complexity sometimes requiring adjunctive modalities such as fulguration, the need for multiple procedures (mean, 2.0 procedures) to effect complete excision, and recurrence rates approaching 30%, with a requirement for continued endoscopic surveillance. Ultimately, choice is driven by availability of local expertise, patient tolerance of or expected compliance with long-term endoscopic surveillance programs, presence or absence of coexisting familial polyposis syndromes, medical comorbidities, and overall life expectancy.

Treatment of ampullary villous adenomas that may harbor carcinoma

Villous adenoma of the ampulla of Vater is a rare tumor. It is a deceptive tumor because it is a premalignant lesion and biopsies of the lesion are false negative in 25% to 56% of patients. The primary focus of this report is 23 of 30 patients with villous adenoma of the ampulla of Vater who underwent Whipple operations. Paraffin blocks from 22 patients were available. In eight patients, blocks of the biopsies and the corresponding resected specimens were available. Immunohistochemical studies using antibodies to p53 and Ki-67 were performed to determine whether accumulation of these antibodies in the biopsy specimens would identify false negative biopsies. There was one operative death. The 2-, 5-, and 10-year survival rates for the 22 patients surviving a Whipple operation were 74%, 57%, and 35%, respectively. Three patients died of cancer. The mean p53 expression index was increased in adenomas to 88 (P = 0.001) and in carcinomas to 114 (P = 0.01), compared with 12.6 for normal ampullary epithelium adjacent to tumor. Significant differences in the Ki-67 proliferation index were noted between normal adjacent epithelium (13%), adenoma (34%, P = 0.0002), and carcinoma (53%, P = 0.034), as well as between adenomatous epithelium and carcinoma (34% vs. 53%, P = .012). Villous ampullary adenocarcinoma was present in 65% of patients with villous adenoma (87% if patients with carcinoma in situ in resected specimens are included). Because of the high false negative rate of ampullary biopsies, and the inability to accurately stage these lesions, we recommend pancreaticoduodenectomy in most patients. Studies with p53 and Ki-67 markers suggest that they may be helpful in the recognition of ampullary villous cancer not identified on routine biopsies.