Differential diagnosis of pancreatobiliary carcinoma from autoimmune pancreatitis-related diseases: a report of three cases.

ABSTRACT

BACKGROUND: "Japanese clinical guidelines for autoimmune pancreatitis" advised to carefully differentiate between two conditions autoimmune pancreatitis (AIP) and associated sclerosing cholangitis (SC), and pancreatobiliary malignancy. METHODOLOGY: We report a series of three cases for which differential diagnosis of pancreatobiliary carcinoma from AIP and associated SC was crucial. RESULT: Three patients presented with biliary stenosis secondary to pancreatic swelling or mass lesion, followed by further examinations Case 1 was first diagnosed as having tumor-forming pancreatitis associated with AIP but eventually proven to be pancreatic head carcinoma; case 2 was operated for suspected bile duct cancer combined with AIP and associated cholangitis, and early cancer was found in the resected specimen; case 3 was operated on for presumed cholangiocarcinoma combined with AIP-associated SC, but no malignancy was found. CONCLUSIONS: Current series of cases would raise an alert on diagnosis of AIP and associated SC, and pancreatobiliary malignancy should be carefully excluded by any means. Surgical intervention would be required in selected cases of this clinical entity.