Gall Bladder Mass-always a Cancer? Think Outside the Box!

Abstract

Background: Gallbladder cancer (GBC) is endemic in northern part of India . Any patient presenting with a gallbladder mass is considered malignant until proved otherwise. Many benign conditions of gallbladder mimic GBC and immunoglobulin G4(IgG4) disease is amongst the rare ones. IgG4 related sclerosing disease is a systemic inflammatory disease with multiorgan involvement. It is attributed to an interplay of autoimmune, genetic and molecular pathways. It is rare and presentation is atypical. Disease can be localized or diffuse type. Diffuse type usually associated with IgG4 sclerosing cholangitis or pancreatitis while localized type of IgG4 cholecystitis can imitate maliganancy. Hence a high index of suspicion is required when the presentation is atypical. Case report: Our patient, a middle aged lady presented with vague right upper abdominal pain with no associated symptoms. On evaluation she was found to have mass lesion in fundus of gallbladder while her liver function, tumour markers (CEA and CA 19-9) and serum IgG4 level was normal. Computed tomography and magnetic resonance imagining was suggestive of a malignant lesion. She underwent anticipatory extended cholecystectomy in view of the same(Fig 1),but final histopathology revealed chronic sclerosing cholecystitis with lymphocytic infilrate and storiform fibrosis, hence IgG4 immunohistochemistry was performed and was positive. Conclusion: IgG4 cholecystitis is exceptionally rare and a difficult diagnosis to make in the pre-operative phase especially since serum IgG4 was normal. Due to uncertanity of diagnosis and aggressive nature of GBC ,timely surgery is prudent and deligent histopathological analysis of resected specimen is pivotal.