IgG4-related liver disease, presenting as a liver tumour (a case report and review of literature)

Abstract

IgG4-related disease is a multisystemic fibroinflammatory condition, although the liver involvement by the disease is rare. The disease is characterised by distinctive histopathologic features, most notably dense lymphoplasmacytic infiltrate, storiform fibrosis, and obliterative phlebitis. The diagnosis should be made only by an interdisciplinary approach to correlate clinical history, pathological picture and radiological findings. We report a case of an 80-year-old male patient presenting with a left lower lobe liver mass. An intrahepatic cholangiocarcinoma was suspected on imaging studies. The patient underwent left hemi-hepatectomy. Macroscopically there was a poorly circumscribed firm tumour measuring up to 47 mm, present within liver parenchyma. Microscopic examination showed dense hyalinised fibrotic hypocellular tissue with fibroblastic proliferation admixed with lymphoplasmacytic infiltrate with focal formation of lymphoid follicles. The entire lesion was then submitted and no malignancy was detected. IgG and IgG4 immunohistochemical stains demonstrated an increase in number of IgG4 positive cells (more than 30 per high power field), as well as an increase in the ratio of IgG4 to IgG positive plasma cells. This immunophenotype is in keeping with IgG4-related liver disease.