Clinical Gastroenterology Vol.33 No.2(7)

Theme Autoimmune Pancreatitis -- Present Status & Future Perspectives
Title Characteristic CT and MRI Findings of Autoimmune Pancreatitis
Publish Date 2018/02
Author Dai Inoue Department of Radiology, Kanazawa University Hospital
Author Fumihito Toshima Department of Radiology, Kanazawa University Hospital
Author Norihide Yoneda Department of Radiology, Kanazawa University Hospital
Author Azusa Kitao Department of Radiology, Kanazawa University Hospital
Author Takahiro Komori Department of Radiology, Kanazawa University Hospital
Author Toshifumi Gabata Department of Radiology, Kanazawa University Hospital
[ Summary ] The diagnosis of autoimmune pancreatitis (AIP) is made by a multidisciplinary approach including clinical, radiological, and pathological examinations. Of these, radiological examinations play an important role in lesion detection and differential diagnosis. Typical AIP showing diffuse enlargement with a capsule‒like rim can be easily diagnosed based on imaging, followed by serum IgG4 evaluation. However, atypical AIP cases have been reported, and they should be differentiated from other conditions, especially pancreatic cancer. Some imaging findings such as speckled enhancement, homogeneous enhancement in late‒phase images, and duct‒penetrating sign could be helpful in this differentiation ; however, in cases where imaging examinations cannot discriminate pancreatic cancer, a more aggressive approach by EUS‒FNA would be mandatory.
As with other aspects of AIP, it is now recognized as a pancreatic manifestation of systemic "IgG4‒related disease" that can involve systemic organs such as lacrimal glands, kidney, and aorta. Thus, clinicians need to be familiar with imaging features of extra pancreatic lesions as well as pancreatic lesion.
back