A Pancreatic Mass With Multiple Hepatic Lesions

Abstract

57-year-old man presented with jaundice, right Aupper-quadrant pain, and weight loss. Ultrasonography reviewed diffuse hypoechoic enlargement of the pancreas and hypoechoic lesions in the right lobe of the liver. Computed tomography showed focal heterogeneous enlargement of the pancreatic head, diffuse pancreatic swelling with hypodense capsule-like rim, and multiple hypoechoic-enhancing masses over bilateral liver lobes (Figure A). A clinical suspicion of pancreatic cancer with hepatic metastasis was raised. Endoscopic biopsy of pancreatic head mass found inflamed necrotic debris with ova of Clonorchis sinesis (Figure B). A targeted liver biopsy showed a fibroinflammatory process with plasma cell-rich chronic inflammatory infiltrate (Figure C), eosinophilic granulomas (Figure D), and increased IgG4-positive plasma cells (Figure E). Subsequent serology showed marked increases of serum IgG and IgG4 levels. A final diagnosis of hepatic inflammatory pseudotumors (IPTs) complicated by IgG4-related autoimmune pancreatitis and Clonorchis infestation was established. A course of praziquantel was prescribed for Clonorchis infestation, and various immunosuppressants were given for IgG4related disease. However, the resolution of pancreatic and liver lesions was slow and fluctuated. Complete resolution finally was achieved after 3.5 years of immunosuppression (Figure F). C sinesis is the most common human liver fluke in East Asia and a well-known risk factor of cholangiocarcinoma. It is uncertain whether Clonorchis infestation contributes to tissue eosinophilia and eosinophilic granuloma in the liver biopsy of our patient because IgG4-related disease may have numerous tissue eosinophils. IgG4-related disease is an increasingly recognized fibroinflammatory disease characterized by tumefactive lesions, storiform fibrosis, IgG4-positive plasma cell-rich lymphoplasmacytic infiltrate, and an often increased serum IgG4 level. It affects virtually every organ: pancreas, salivary glands, liver, kidneys, lungs, lymph nodes, meninges, aorta, breast, prostate,