Common features between neoplastic and preneoplastic lesions of the biliary tract and the pancreas

the bile duct system and pancreas show many similarities due to their anatomical proximity and common embryological origin.Consequently,preneoplastic and neoplastic lesions of the bile duct and pancreas share analogies in terms of molecular,histological and pathophysiological features.Intraepithelial neoplasms are reported in biliary tract,as biliary intraepithelial neoplasm(BilIN),and in pancreas,as pancreatic intraepithelial neoplasm(PanIN).Both can evolve to invasive carcinomas,respectively cholangiocarcinoma(CCA)and pancreatic ductal adenocarcinoma(PDAC).Intraductal papillary neoplasms arise in biliary tract and pancreas.Intraductal papillary neoplasm of the biliary tract(IPNB)share common histologic and phenotypic features such as pancreatobiliary,gastric,intestinal and oncocytic types,and biological behavior with the pancreatic counterpart,the intraductal papillary mucinous neoplasm of the pancreas(IPMN).All these neoplastic lesions exhibit similar immunohistochemical phenotypes,suggesting a common carcinogenic process.Indeed,CCA and PDAC display similar clinic-pathological features as growth pattern,poor response to conventional chemotherapy and radiotherapy and,as a consequence,an unfavorable prognosis.The objective of this review is to discuss similarities and differences between the neoplastic lesions of the pancreas and biliary tract with potential implications on a common origin from similar stem/progenitor cells.

Feasibility of therapeutic endoscopic ultrasound in the bridge-to-surgery scenario:The example of pancreatic adenocarcinoma

Upfront resection is becoming a rarer indication for pancreatic ductal adenocarcinoma,as biologic behavior and natural history of the disease has boosted indications for neoadjuvant treatments.Jaundice,gastric outlet obstruction and acute cholecystitis can frequently complicate this window of opportunity,resulting in potentially deleterious chemotherapy discontinuation,whose resumption relies on effective,prompt and long-lasting management of these complications.Although therapeutic endoscopic ultrasound(t-EUS)can potentially offer some advantages over comparators,its use in potentially resectable patients is primal and has unfairly been restricted for fear of potential technical difficulties during subsequent surgery.This is a narrative review of available evidence regarding EUS-guided choledochoduodenostomy,gastrojejunostomy and gallbladder drainage in the bridge-to-surgery scenario.Proof-ofconcept evidence suggests no influence of t-EUS procedures on outcomes of eventual subsequent surgery.Moreover,the very high efficacy-invasiveness ratio over comparators in managing pancreatic cancer-related symptoms or complications can provide a powerful weapon against chemotherapy discontinuation,potentially resulting in higher subsequent resectability.Available evidence is discussed in this short paper,together with technical notes that might be useful for endoscopists and surgeons operating in this scenario.No published evidence supports restricting t-EUS in potential surgical candidates,especially in the setting of pancreatic cancer patients undergoing neoadjuvant chemotherapy.Bridge-to-surgery tEUS deserves further prospective evaluation.