Focal autoimmune pancreatitis and chronic sclerosing sialadenitis mimicking pancreatic cancer and neck metastasis

Type 1 autoimmune pancreatitis(AIP)or chronic sclerosing sialadenitis(Küttner’s tumour)is an uncommon disorder that has recently been confirmed as an Ig G4-related disease.Here,we describe a rare case of a53-year-old male patient who primarily presented with pancreatic body mass,left neck mass and several lumps in his lower lip mimicking pancreatic cancer(PC)and neck metastasis.The patient underwent pancreatic body mass and labial gland lumps resection as well as an ultrasound-guided biopsy of the left neck mass.He was diagnosed with Ig G4-related focal type of AIP(f-AIP)and Küttner’s tumour by immunohistochemistry.The patient responded well to corticosteroid therapy andremains healthy with no signs of recurrence at one year follow-up.The differentiation of f-AIP from PC is very important to avoid unnecessary pancreatic resection.