TITLE:
IgG4-Unrelated Type 1 Auto Immune Pancreatitis Manifesting with Pancreatic Head Mass Mimicking Cancer
AUTHORS:
Adnane Arrami, Nabil Moatassim Billah, Tarik Addioui, Ittimad Nassar
KEYWORDS:
Autoimmune Pancreatitis (AIP), Pancreatic Head Mass, Pancreatic Cancer (PC), Ig4 Unrelated, Imaging Features
JOURNAL NAME:
Open Journal of Clinical Diagnostics,
Vol.8 No.2,
June
28,
2018
ABSTRACT:
Auto immune pancreatitis
(AIP) is an uncommon form of chronic pancreatitis that has been divided into type 1 and type 2 which have distinct
histopathology and clinical features. Type 1 AIP seems to be the pancreatic
manifestation of an IgG4-related systemic disease, characterized by elevated
IgG4 serum levels, infiltration of IgG4-positive plasma cells and extrapancreatic
lesions. When manifesting as a focal disease in the pancreas, it can be
challenging to differentiate it from pancreatic cancer (PC). Because AIP is
typically responsive to steroid therapy without the need for resection,
differentiation between these two diseases is critical. We report the case of a
56-year-old man with initial suspect of PC, and final diagnosis of type 1 AIP
according to the International Consensus Diagnostic Criteria (ICDC) without
elevated levels of serum IgG4 or need for a histology sample. We take a review
of literature in order to improve the diagnostic accuracy of AIP and describe
clinical and imaging features to differentiate it from PC and avoid unnecessary
surgery due to misdiagnosis.