Pancreatic Ductal Adenocarcinoma Associated with Autoimmune Pancreatitis

Autoimmune pancreatitis (AIP), in contrast to other benign chronic pancreatic diseases, can be cured with immunosuppressant drugs, thus the differentiation of AIP from pancreatic cancer is of particular interest in clinical practice. There is the possibility that some patients with AIP may develop pancreatic cancer, and this possibility contributes to increasing our difficulties in differentiating AIP from pancreatic cancer. We herein report the case of a 70-year-old man in whom pancreatic adenocarcinoma and AIP were detected simultaneously. We must carefully monitor AIP patients for the simultaneous presence of pancreatic cancer, even when a diagnosis of AIP is confirmed

IgG4-related kidney diseases and conditions: Renal pelvic and ureteral diseases

In the literature on IgG4-related urinary tract diseases, reports of cases with involvement of the renal pelvis and ureters are increasing. IgG4-related renal pelvic and ureteral lesions accompany extra-renal organ involvement, including IgG4-related type 1 autoimmune pancreatitis, sialadenitis, and orbital disease, and are characterized by the common pathological features of IgG4-related disease (IgG4-RD), including substantial numbers of IgG4-positive plasma cells, storiform fibrosis, and stenosis in the affected organs. Similar to other mucosal organs affected in IgG4-RD, these inflammatory findings are observed within the fibroadipose tissue in the renal hilum and around the ureters. The urothelial epithelium covering the renal pelvis and ureter is preserved. Nodular lesions such as pseudotumors can also form and it is important to differentiate these from malignant tumors. At present, comprehensive diagnostic criteria that include pathological parameters have been proposed for IgG4-RD; however, obtaining diagnostic findings in small biopsy specimens is often challenging. Therefore, the diagnosis can only be rendered following careful consideration of the patient’s clinical, serologic, radiologic, and pathologic features, including the possibility of involvement in other organs. © Springer Japan 2016.[Book Chapter

IgG4-Related Diseases and the Liver

IgG4-related disease (IgG4-RD) is a systemic illness including autoimmune pancreatitis and IgG4-related sclerosing cholangitis (IgG4-SC). Although hepatic presentation of IgG4-RD has been reported, whether intrahepatic small bile ducts and hepatocytes are direct targets of IgG4-RD is uncertain. IgG4-RD is pathologically characterized by the numerous IgG4+ cells found in affected organs, but this IgG4 positivity is also frequently found in extrahepatic cholangiocarcinoma and is prominent, albeit rarely, in other hepatobiliary diseases including primary sclerosing cholangitis and autoimmune hepatitis. Moreover, cholangiocarcinoma arising from precedent IgG4-SC and IgG4-SC accompanying precursor lesions of cholangiocarcinoma (biliary intraepithelial neoplasia) are also reported. Diagnostic criteria for IgG-RD and IgG4-SC were recently proposed, but each individual case should be diagnosed clinicopathologically on the basis of its individual features. © Springer Japan 2016.[Book Chapter