Immunoglobulin G4-related sclerosing cholangitis in patients resected for presumed malignant bile duct strictures

Background: Immunoglobulin (Ig) G(4)-related lymphoplasmacytic sclerosing pancreatitis has been described in the context of autoimmune pancreatitis mimicking distal cholangiocarcinoma. The aim of this study was to assess the occurrence of this entity in benign bile duct strictures in patients resected for presumed hilar cholangiocarcinoma. Methods: Of 185 patients who had undergone resection of proximal bile ducts on suspicion of hilar cholangiocarcinoma between January 1984 and June 2005, 32 (17.3 per cent) had a benign bile duct stricture on histopathological examination. After re-evaluation, further immunohistochemical analysis was performed on specimens from patients with features of autoimmune-like disease. Results: The Periductal stroma in 15 patients showed features of autoimmune-like disease (diffuse, moderate to severe lymphoplasmacytic infiltration with marked fibrosis). Abundant IgG(4)-positive plasma cell infiltration around the bile duct lesions was seen in two of these. Although not significant, patients with features of autoimmune-like disease on histological changes showed a higher incidence of recurrent biliary complications than those without (P = 0.250). Conclusion: Features of autoimmune-like bile duct disease were seen in almost half (15 of 32) of patients with benign hilar strictures resected for presumed hilar cholangiocarcinoma. Frank IgG(4)-related sclerosing disease was found in only two of the 15 patients with autoimmune-like bile duct disease.