The purpose of the study is to assess the efficacy and morbidity of biliairy radiofrequency ablation for the treatment of dysplastic endobiliairy residual lesions (low-grade dysplasia or high-grade dysplasia) after endoscopic ampullectomy for ampullary adenoma.

Neoplastic lesions may persist at the termination of the common bile duct or pancreatic duct, after endoscopic ampullectomy for adenoma. Such lesions conduct to a difficult therapeutic problem because surgery (pancreaticoduodenectomy or trans-duodenal resection) has significant morbidity compared to non-invasive lesions. The use of endoscopic destruction techniques of dysplastic lesions, including radio-frequency could be an interesting alternative to reduce the risk of invasive cancer with less morbidity. Ablation with radio-frequency (RF) is a technique of local tissue destruction in use in many applications, percutaneously or intraoperatively for the treatment of hepatocellular carcinoma smaller and more recently for the endoscopic treatment of high-grade dysplasia of Barrett's esophagus. An RF probe has been developed for an endo-biliary application (Habib EndoHPB, Emcision) and 2 preliminary studies have reported the use in humans, in the indication of unresectable cholangiocarcinoma. These two studies have confirmed the feasibility of the technique, with few side effects and probable anti-tumor efficacy demonstrated by expanding the area of stenosis after treatment.

Inclusion Criteria:

• Presence of lesions of low-grade dysplasia (LGD) or high grade (HGD) in the common bile duct, confirmed by two pathological readings in relation to residual adenomatous tissue into the common bile duct after endoscopic ampullectomy for ampullome conducted in the previous year
• Lack of residual adenomatous lesion on the duodenal side after ampullectomy and possibly additional procedures (endoscopic mucosal resection or argon plasma). (excluding other duodenal adenomatous lesions in the context of familial adenomatous polyposis
• Consultative multidisciplinary digestive cancer meeting confirming the indication of treatment with endo-biliary radio-frequency
• Dysplastic lesions extending over 20 mm length maximum in the common bile duct
• Patients aged ≥ 18 years old and ≤ 85 years old
• Patients who consented to participate in the study
• No anesthesia contraindication (ASA 1,2,3)
• Patient affiliated to a social security scheme (beneficiary or legal)
• Lack of pregnancy and contraception being women age procreate

Exclusion Criteria:

• Lesions of invasive carcinoma in a patient whose clinical condition allows to consider a pancreaticoduodenectomy
• Endo-biliary dysplastic lesions diffuse or multifocal
• Presence of non extractable metal biliary expansive prosthesis
• History of pancreaticoduodenectomy or hepaticojejunostomy anastomosis
• Impassable stenosis of the common bile duct
• Severe coagulopathy, thrombocytopenia < 75,000 G/L , Clopidogrel treatment impossible to stop temporarily
• Anesthesia contraindication ( ASA 4)
• Pace maker or other active implantable medical device
• Inability to obtain informed consent