Autoimmune pancreatitis or pancreatic cancer? A dilemma in a pregnant woman.

Introduction: Autoimmune pancreatitis is now a defined entity and it could mimic a pancreatic malignancy. True oncological emergencies in pregnant patients are rare.

Case Report: A 39 years-old pregnant woman was admitted to our emergency unit due to right upper quadrant abdominal pain and evidence of obstructive jaundice. Since computed tomography-scan and endoscopic retrograde cholangiopancreatography are contraindicated in pregnant woman, a cholangio-Nuclear Magnetic Resonance was performed, confirming the biliary tract dilatation with stenosis of the intrapancreatic portion of the common bile duct and a shaded image of a mass in the pancreatic head. An endoscopic ultrasound with fine needle aspiration biopsy were performed. US-guided external percutaneous trans-hepatic biliary drainage was successfully performed. The cytological examination showed the presence of erythrocytes, granulocytes, histiocytes and rare lymphocytes; a diagnosis of AIP was supposed, and steroid therapy with metilprednisolone was started. Laboratory tests and jaundice were normalized within 15 days, and the fetus was born in very good health, 22 weeks after. The follow-up was uneventful and a CT-scan confirmed the complete normalization of the pancreatic gland, 12 months after hospital discharge.

Conclusion: Autoimmune pancreatitis should be taken into account in the differential diagnosis of a not well defined pancreatic mass; in the event of pancreatic mass-forming disease in pregnancy, the differential diagnosis should be early and accurate, because destructive surgery involves an high rate of morbidity and may interrupt pregnancy. A US-guided FNAB and the response to the corticosteroid therapy should lead to a correct diagnosis.