The patient has the classic clinical, endoscopic, and radiographic appearance of an intraductal papillary mucinous tumor, a lesion that can undergo malignant transformation. A cholangiocarcinoma would arise from the bile duct, not the pancreatic duct. A mucinous cystadenocarcinoma would not arise from a side branch of the pancreatic duct. Neither a pancreatic adenocarcinoma nor a pseudocyst would secrete mucus into the pancreatic duct.
