Infiltration of peritumoural but tumour-free parenchyma with IgG4-positive plasma cells in hilar cholangiocarcinoma and pancreatic adenocarcinoma.

Abstract

Recently, new guidelines for diagnosing IgG4-associated cholangitis have been published devaluing the diagnostic significance of IgG4-positive plasma cells and steroid trials. We sought to evaluate the utility of IgG4-positive plasma cells in discriminating IgG4-associated cholangitis from hilar cholangiocarcinoma and autoimmune pancreatitis from pancreatic adenocarcinoma under conditions when malignancy is likely to be missed.