Fig. 4From: Focal IgG4-related autoimmune pancreatitis with distal choledochal adenocarcinoma: a rare case reportHistological findings of tumor-forming pancreatitis without a background of typical chronic pancreatitis. a Tumor lesions manifested as lymphoid hyperplasia, germinal centers, lymphoplasmacytic infiltration, and interlobular and intralobular fibrosis. Hematoxylin and Eosin (HE), original magnification: 100 ×. b Immunohistochemical study showing positive immunoreactivity for IgG4 in the plasma cells. More than 90 IgG4-positive plasma cells/high power field were detected. Original magnification: 200 ×Back to article page