Pancreatic mucin-producing adenocarcinoma associated with a pancreatic stone: report of a case

We present an autopsy case of an 83-year-old Japanese man with a mucin-producing adenocarcinoma accompanied by pancreatolithiasis in the head of the pancreas. He suffered from obstructive jaundice and died of disseminated intravascular coagulation. He did not normally drink alcohol and had no history of chronic pancreatitis. The autopsy findings revealed a mucinous cystic tumor, composed of multiple dilatated branches, in the head of the pancreas. Histological examinations showed papillary adenocarcinoma, which scirrhously infiltrated the distal common bile duct with perineural invasion and lymph node involvement. He was thus diagnosed to have mucin-producing branch-type cancer in the head of the pancreas. The main pancreatic duct was dilated, and the residual pancreatic tissue showed moderate fibrosis and parenchymal atrophy. A stone was observed in a dilated branch of the primary lesion. To the best of our knowledge, there have only been five previously reported cases of mucin-producing tumor associated with pancreatolithiasis. Intraductal calcification is a major characteristic of chronic pancreatitis, but it is clinically important not to misdiagnose cancers associated with pancreatolithiasis such as chronic pancreatitis.