Steroid-resistant Relapse of Autoimmune Pancreatitis with Marked Main Pancreatic Duct Dilatation Mimicking Multifocal Pancreatic Cancer.
Kenji Hirano, Kanami Kondo, Toshifumi Saito et al.
✦ AI-curated · Sources linked
Case in brief
A 67-year-old man with type 1 autoimmune pancreatitis and IgG4-related sclerosing cholangitis relapsed with pancreatic head swelling and distal bile duct stenosis. The disease worsened despite increasing prednisolone from 7.5 to 20 mg/day. Imaging showed marked main pancreatic duct dilatation (8 mm) and a new pancreatic tail duct stenosis, raising concern for multifocal pancreatic cancer. Repeated endoscopic ultrasound-guided fine-needle aspiration biopsies did not identify malignancy. After prednisolone was increased to 40 mg/day, clinical and radiological findings improved.
What made this case unusual
The relapse produced marked main duct dilatation and a new tail duct stenosis, an appearance that mimicked multifocal pancreatic cancer despite the underlying autoimmune pancreatitis.
Diagnostic / clinical pearl
When autoimmune pancreatitis worsens despite an initial steroid increase and imaging raises concern for cancer, malignancy should be evaluated before further intensifying immunosuppression.