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Endoscopic papillectomy has been increasingly used in the treatment of ampullary neoplasms. These include adenomas, carcinomas, and neuroendocrine tumors. On the basis of endoscopic appearance alone, ampullary adenomas cannot always be distinguished from other lesions. In pathology series of specimens submitted after endoscopic papillectomy, 24% of them consisted of normal histology or reactive atypia. Ampullary adenomas can occur sporadically or in association with genetic syndromes such as familial adenomatous polyposis (FAP). The natural history of sporadic ampullary adenomas is undefined. Adenomas associated with FAP have a more benign course. There is no definitive guideline on the size of adenomas beyond which endoscopic resection should not be attempted. There are case series of endoscopic resection of large lateral spreading tumors in the duodenum. Adenomas with high dysplasia warrant endoscopic removal. EUS and intraduct ultrasound allow for assessment of ductal extension, involvement of muscularis propria and regional nodal status. At ERCP, both biliary and pancreatic ducts should be evaluated for possible ductal extension. Most endoscopists would consider ductal extension as an indication for surgery. Techniques of endoscopic papillectomy have not been standardized. Some advocate submucosal injection with fluids such as epinephrine, or methylcellulose. En bloc resection is preferred although piecemeal resections are often required for larger lesions. Most would attempt cannulation of both ducts prior to snare papillectomy. Some would leave a wire in the pancreatic duct and ensnare the lesion over a guidewire. Some would mix methylene blue with contrast while obtaining a pancreatogram to ‘tattoo’ the duct for subsequent stenting. After a snare papillectomy, one small randomized controlled study showed that the insertion of a pancreatic stent reduced the rate of pancreatitis. A biliary sphincterotomy should be performed to ensure adequate biliary drainage. Intervals for post resection surveillance have not been defined. Lesions with high grade dysplasia should be followed up closely. Papillectomy should probably not be considered as a substitution to pancreatico-duodenectomy (PD) in early carcinoma (T1 or Tis). In surgical series, a third of patients with Tis or T1 disease had at least one risk factor for failure to papillectomy. These included lymph node metastasis (9%), perineural invasion (1.5%) or tumor extension along either the bile duct or pancreatic duct beyond the sphincter of oddi (22%). In another surgical series of 450 patients with ampullary carcinoma who underwent PD, the incidence of lymph node metastasis was 28% in those with T1 lesions. |
