Intraductal Papillary Neoplasm of the Bile Duct With Invasive Adenocarcinoma Complicating IgG4-related Sclerosing Cholangitis: Report of a Case

Abstract

Although there have been many previous studies of IgG4-related SC focusing on the differential diagnosis from cholangiocarcinoma, only a few patients with cholangiocarcinoma against a background of IgG4-related SC have been reported. We herein present a case of intraductal papillary neoplasm of the bile duct (IPNB) associated with invasive carcinoma complicating IgG4-related sclerosing cholangitis. A 71-year-old female with icterus was admitted to a local hospital, where stricture of the extrahepatic bile duct were detected, and subsequently referred to our hospital for possible surgery. Abdominal multidetector-row computed tomography demonstrated marked wall thickening along the entire extrahepatic bile duct. The left lateral superior bile duct (B2) and left lateral inferior duct (B3) were individually obstructed, and percutaneous transhepatic biliary drainage catheters were placed in B2 and B3 separately. The patient was diagnosed to have diffusely spread cholangiocarcinoma and underwent right hepatic trisectionectomy with caudate lobectomy and pancreatoduodenectomy. A histological examination revealed intraductal papillary tumors composed of fibrovascular stalks covered by neoplastic epithelium. Carcinomatous invasion of the papillary tumors was observed in the fibromuscular layer, and there was abundant infiltration of inflammatory cells with fibrosis outside of the cancerous tissue. The inflammatory cells were primarily composed of plasma cells, a majority of which were positive for IgG4 (>30 cells/high-power field); the postoperative serum IgG4 level was 890 mg/dL. Therefore, a diagnosis of coexisting IPNB associated with invasive carcinoma and IgG4-related sclerosing cholangitis was made. To the best of our knowledge, this is the first report of IPNB complicating IgG4-related sclerosing cholangitis.