He is a widely recognized expert in pancreatic and biliary surgery, and has authored over 350 publications on pancreatic cancer, cystic tumors of the pancreas, Intraductal papillary mucinous neoplasms (IPMN), neuroendocrine pancreatic tumors, acute and chronic pancreatitis. For several years he has performed the largest number of pancreatic resections in New England. He serves in the editorial board many journals, including Annals of Surgery and Pancreatology, and is a past president of the American Pancreatic Association.