[An IgG4-related pancreatitis mimicking an adenocarcinoma: A case report]

Early pancreatic cancer in IgG4-related pancreatic mass: A case report

BACKGROUND

IgG4-related disease can manifest diversely, including autoimmune pancreatitis and IgG4-related cholangiopathy. We are reporting a very unusual cause of pancreatic cancer triggered in a previously unknown IgG4-related disease.

CASE SUMMARY

A 75-year-old man was diagnosed with a 43 mm × 33 mm pancreatic head tumor after consulting for abdominal pain and jaundice. A pancreaticoduodenectomy was carried out uneventfully, and the histopathology report showed an early stage of acinar-cell pancreatic cancer. The patient reconsulted on the 30^th postoperative day with fever, jaundice and asthenia. Magnetic resonance cholangiopancreatography evidenced an extense bile duct stricture. A percutaneous biliary drainage proved to be ineffective, even after exchanging it with larger bore drainage. Reviewing the surgical specimen, features compatible with IgG4-related disease were observed. Consequently, empiric treatment with steroids was initiated achieving excellent results.

CONCLUSION

IgG4-related disease may cause chronic inflammation of the pancreas and can condition pancreatic malignancies.

A Case of Type 1 Autoimmune Pancreatitis (AIP), a Form of IgG4-Related Disease (IgG4-RD)

BACKGROUND Type 1 autoimmune pancreatitis (AIP), also known as lymphoplasmacytic sclerosing pancreatitis (LPSP), is a rare cause of chronic pancreatitis, characterized by a fibro-inflammatory process. However, patients with AIP may have a good response to corticosteroid therapy. We describe a Tunisian patient with AIP that was confirmed to be an IgG4-related disease (IgG4-RD). CASE REPORT We describe a case of a 70-year-old man who was admitted to hospital for obstructive jaundice and abdominal pain. Serum liver function tests were abnormal and upper abdominal computed tomography (CT) imaging showed diffuse pancreatic swelling and strictures of the main pancreatic duct without any focal lesion. Pancreatico-biliary magnetic resonance imaging (MRI) showed a thickened rim surrounding the pancreatic duct Serum IgG4 levels were elevated, resulting in a diagnosis of IgG4-related AIP. The patient showed a good clinical, biochemical, and radiological response following steroid therapy in combination with azathioprine. CONCLUSIONS The diagnostic workup of IgG4-RD is complex and usually requires a combination of clinical examination, imaging, and serological analysis. As this case report has demonstrated, IgG4-RD should be considered in patients who present with pancreatitis or AIP, because of the favorable response to steroid therapy, particularly when treatment is initiated early.