Kazuyoshi Katayanagi

Igg4-related Sclerosing Cholangitis With and Without Hepatic Inflammatory Pseudotumor, and Sclerosing Pancreatitis-associated Sclerosing Cholangitis: Do They Belong to a Spectrum of Sclerosing Pancreatitis?

Sclerosing cholangitis (SC) is a heterogeneous disease entity. Different etiologies such as choledocholithiasis, biliary tumor, or pericholangitis can manifest as SC. Hepatic inflammatory pseudotumor (IP) is rarely associated with SC (sclerosing cholangitis associated with hepatic inflammatory pseudotumor; SC-hepatic IP), but sclerosing pancreatitis (SP) is not infrequently associated with bile duct lesions (sclerosing pancreatitis-associated sclerosing cholangitis; SP-SC). In this study, we compared the histologic changes of hepatic hilar and extrahepatic bile duct lesions of SC (7 cases), SC-hepatic IP (5 cases), SP-SC (5 cases), and typical primary sclerosing cholangitis (PSC) (5 cases). Histologically, all SP-SC cases showed extensive and dense fibrosis with marked lymphoplasmacytic infiltration, many eosinophils, and obliterative phlebitis. Four cases of SC showed bile duct lesions similar to those of SP-SC, whereas other three cases of SC showed milder lymphoplasmacytic infiltration, scant eosinophilic cell infiltration, and no obliterative phlebitis. All SC-hepatic IP cases showed bile duct lesions identical to those of SP-SC. Immunohistochemically, many IgG4-positive plasma cells were found in the bile duct lesions of all SP-SC cases, 4 SC cases with marked lymphoplasmacytic infiltration, and all SC-hepatic IP cases. By contrast, IgG4-positive plasma cells were scarce or hardly found in the remaining 3 SC cases and all PSC cases. In conclusion, 4 SC cases and all SC-hepatic IP cases showed bile duct lesions identical to those of SP-SC, suggesting that these three conditions may be a single disease entity. Their pathogenesis may be similar or closely related to that of SP, and in that respect they may represent an IgG4-related biliary disease. They may respond to steroid therapy as SP does.

Abundant IgG4-positive plasma cell infiltration characterizes chronic sclerosing sialadenitis (Kuttner's tumor)

Chronic sclerosing sialadenitis (CSS) is a cryptogenic tumor-like condition of the salivary gland(s). While immune-mediated processes are suspected in its pathogenesis, and CSS is occasionally reported to be associated with sclerosing pancreatitis, an IgG4-related disease, the exact immunopathologic processes of CSS remain speculative. In this study, we examined the clinicopathologic findings of CSS (12 cases) in comparison with sialolithiasis (8 cases) and Sjögrens syndrome (13 cases), and tried to clarify whether CSS is an IgG4-related disease or not. Submandibular gland(s) were affected in all cases of CSS. CSS cases could be divided into two types: 5 cases were associated with sclerosing lesions in extrasalivary glandular tissue (systemic type), while only salivary gland(s) were affected in the remaining 7 cases (localized type). In the former type, which showed male predominance, bilateral salivary glands were frequently affected, and eosinophilia and elevations of γ-globulin and IgG in serum were frequently found. Histologically, all cases of CSS showed marked lymphoplasmacytic infiltration admixed with fibrosis and the destruction of glandular lobules. Obliterative phlebitis was found in the affected salivary glands in all cases of CSS. Immunohistochemically, the proportion of IgG4/IgG-positive plasma cells was more than 45% in CSS, while it was less than 5% in controls. The resemblance of the clinicopathologic features of CSS with those of sclerosing pancreatitis suggests the participation of a similar immunopathologic process with IgG4 disturbance in CSS. The abundance of IgG4-positive plasma cells in the lesions would be useful for distinguishing CSS from other forms of sialadenitis.

Biliary Papillary Tumors Share Pathological Features With Intraductal Papillary Mucinous Neoplasm of the Pancreas

Recently, attention has been drawn to papillary neoplasm of the pancreatobiliary systems. In the pancreas, the disease entity of intraductal papillary mucinous neoplasm (IPMN‐P) is widely recognized. In contrast, the pathological characteristics of biliary papillary tumors, such as biliary papilloma(tosis) and papillary cholangiocarcinoma, have not yet been well documented. In this study, we compared the pathological features and post‐operative prognosis among biliary papillary tumors (10 cases of biliary papilloma(tosis) and 22 cases of papillary cholangiocarcinoma), conventional non‐papillary cholangiocarcinoma (15 cases), and IPMN‐P (31 cases). Macroscopically, all biliary papillary tumors were characterized by the prominent intraductal papillary proliferation, and macroscopic mucin‐hypersecretion was seen in 9 of 32 cases (28%). Histologically, biliary papillary tumors consisted of three types of tumor cells (pancreaticobiliary, intestinal and gastric types), whereas only the pancreaticobiliary type was observed in non‐papillary cholangiocarcinoma. Immunohistochemically, biliary papillary tumors were characterized by the common expression of MUC2, CDX2 and cytokeratin 20. In addition, biliary papillary tumors could be associated with two types of invasive lesions: tubular adenocarcinoma (9 cases) and mucinous carcinoma (5 cases). Patients with tubular adenocarcinoma had a poor prognosis compared to non‐invasive papillary tumor or papillary tumor with mucinous carcinoma. These pathological characteristics and the survival status of biliary papillary tumors were different from those of non‐papillary cholangiocarcinoma, and rather closely resembled those of IPMN‐P. In conclusion, biliary papillary tumors may be the biliary counterpart (intraductal papillary neoplasm of the bile duct) of IPMN‐P. (HEPATOLOGY 2006;44:1333–1343.)

Regular ArticlesLipopolysaccharide Induces Overexpression of MUC2 and MUC5AC in Cultured Biliary Epithelial Cells: Possible Key Phenomenon of Hepatolithiasis

Bacterial infection, bile stasis, mucin hypersecretion, and an alteration of the mucin profile such as an aberrant expression of gel-forming apomucin (MUC2 and MUC5AC) in the intrahepatic biliary tree are thought to be important in the lithogenesis of hepatolithiasis. So far, there have been no detailed studies linking bacterial infection to altered mucus secretion of biliary epithelium. In this study, the influence of lipopolysaccharide (LPS), a bacterial component, on apomucin expression in cultured murine biliary epithelial cells was examined with emphasis on the participation of tumor necrosis factor (TNF)-alpha. It was found that LPS up-regulated the expression of MUC2 and MUC5AC in cultured murine biliary epithelial cells. LPS also induced the expression of TNF-alpha in biliary epithelial cells and its secretion into the culture medium. The up-regulation of these apomucins was inhibited by pretreatment with TNF-alpha antibody. TNF-alpha alone also induced the overexpression of MUC2 and MUC5AC in cultured biliary epithelial cells. This overexpression was inhibited by pretreatment with calphostin C, an inhibitor of protein kinase C. These findings suggest that LPS can induce overexpression of MUC2 and MUC5AC in biliary epithelial cells via synthesis of TNF-alpha and activation of protein kinase C. This mechanism might be involved in the lithogenesis of hepatolithiasis.

Epithelial-mesenchymal transition induced by biliary innate immunity contributes to the sclerosing cholangiopathy of biliary atresia

Infections of Reoviridae consisting of a double‐stranded RNA (dsRNA) genome and the biliary innate immune response to dsRNA are implicated in the aetiopathogenesis of biliary atresia (BA). Epithelial–mesenchymal transition (EMT) has recently been proposed as a mechanism behind the sclerosing cholangitis in BA. We hypothesized that the innate immune response to dsRNA in biliary epithelial cells plays an important role in peribiliary fibrosis via biliary EMT. Experiments using cultured human biliary epithelial cells revealed that stimulation with poly(I : C) (a synthetic analogue of viral dsRNA) increased the expression of basic fibroblast growth factor (bFGF, an EMT‐inducer), S100A4 (a mesenchymal marker) and Snail (a transcriptional factor), and decreased that of epithelial markers (biliary‐type cytokeratin 19 and E‐cadherin) and Bambi (TGF‐β1 pseudoreceptor). The expression of TGF‐β1 (EMT‐inducer) and vimentin (a mesenchymal marker) was not affected by poly(I : C). Both EMT‐inducers, bFGF and TGF‐β1, evoked a decrease and increase in the expression of the epithelial markers and of vimentin respectively, and the expression of Bambi was down‐regulated on stimulation with bFGF. Combined treatment with bFGF and TGF‐β1 quickly and completely induced a transformation of morphology as well as change from epithelial to mesenchymal features in cultured biliary epithelial cells. Immunohistochemistry revealed that biliary epithelial cells lining extrahepatic bile ducts and peribiliary glands in BA frequently show a lack of epithelial markers and an aberrant expression of vimentin. Moreover, the biliary epithelium showing sclerosing cholangitis expressed bFGF accompanied by bFGF‐positive mononuclear cells. In conclusion, the EMT may contribute to the histogenesis of sclerosing cholangiopathy, and the biliary innate immune response to dsRNA viruses induces biliary epithelial cells to undergo EMT via the production of bFGF and the increased susceptibility to TGF‐β1 caused by the down‐regulation of Bambi expression. Copyright

Solitary fibrous tumor in the pelvic cavity with hypoglycemia: report of a case.

A case of solitary fibrous tumor (SFT) in the pelvic cavity with hypoglycemia is reported. The patient was a 60-year-old man who was referred to our hospital for a closer examination of hypoglycemia. Computed tomography demonstrated a mass, measuring 14 × 9 cm in size, in the pelvic cavity. Magnetic resonance imaging showed the mass to have a low signal intensity on T1-weighted images and a high intensity on T2-weighted images. Laparotomy revealed no peritoneal dissemination nor lymph node metastasis. An en bloc excision of the tumor was performed with a good recovery, and the hypoglycemia disappeared. Histologically, the tumor was composed of spindle-shaped and oval cells in sarcoma, based on a moderate mitotic rate and cellularity. Immunohistochemically, the tumor was positive for CD34 and negative for keratin, α-smooth muscle actin, desmin, S100 protein, c-kit protein, and epithelial membrane antigen. Based on these findings, the tumor was diagnosed to be malignant SFT in the pelvic cavity.

Surgical resection of recurrent bilateral mediastinal liposarcoma through the clamshell approach

Primary mediastinal liposarcoma is an unusual variant of mediastinal neoplasms. We describe a long-term survivor who underwent repeated operations. After resections through a posterolateral thoracotomy and median sternotomy, a third operation was performed for recurrent bilateral huge tumors through a clamshell incision, and both tumors were removed en bloc. Results of pathologic examination showed that both tumors were well-differentiated liposarcoma. The patient is currently well 16 years after the first operation. Aggressive surgical intervention whenever possible appears to improve the quality of life and prolong the survival of patients with mediastinal liposarcoma.

Clinicopathological significance of antinuclear antibodies in non‐alcoholic steatohepatitis

Aim:  Serum antinuclear antibodies (ANA) are occasionally noted in patients with non‐alcoholic steatohepatitis (NASH). We examined the significance of ANA in NASH.

Intrahepatic cholangiocarcinoma with multicystic, mucinous appearance and oncocytic change

A case is reported herein of intrahepatic cholangiocarcinoma (ICC) with multicystic, mucinous appearance and oncocytic change. Because of liver dysfunction, a 73‐year‐old woman was hospitalized in early October 2003. She was diagnosed as having ICC of the right hepatic lobe with occlusion of the hilar and perihilar bile ducts by imaging examination. Extended right lobectomy was performed but the patient died of liver failure on the next day. In surgically resected specimens, the tumor (3 × 3 cm) was mainly located in the right lobe, and tumors infiltrated along the biliary tree as well as invading into the adjacent hepatic parenchyma. The tumor mass had a sponge or honeycomb appearance. Microscopically, these tumors were composed of multiple microcysts filled by abundant mucin and lined by micropapillary adenocarcinoma cells. Their cytoplasm was acidophilic, appearing as an oncocyte, and carcinoma cells were positive for mitochondrial antigen in addition to biliary cytokeratins. There were no ovarian‐like stromas around these cystic tumors, and communication of the biliary lumen with these carcinomatous cysts was not evident, thus different from biliary mucinous cystadenocarcinoma and intraductal papillary neoplasm of the liver. This is the third case of multicystic mucinous ICC and the present case might have been derived from intrahepatic peribiliary glands.

Preoperative endoscopic diagnosis of superficial non-ampullary duodenal epithelial tumors, including magnifying endoscopy.

Superficial non-ampullary duodenal epithelial tumor (SNADET) is defined as a sporadic tumor that is confined to the mucosa or submucosa that does not arise from Vaters papilla, and it includes adenoma and adenocarcinoma. Recent developments in endoscopic technology, such as high-resolution endoscopy and image-enhanced endoscopy, may increase the chances of detecting SNADET lesions. However, because SNADET is rare, little is known about its preoperative endoscopic diagnosis. The use of endoscopic resection for SNADET, which has no risk of metastasis, is increasing, but the incidence of complications, such as perforation, is significantly higher than in any other part of the digestive tract. A preoperative diagnosis is required to distinguish between lesions that should be followed up and those that require treatment. Retrospective studies have revealed certain endoscopic findings that suggest malignancy. In recent years, several new imaging modalities have been developed and explored for real-time diagnosis of these lesion types. Establishing an endoscopic diagnostic tool to differentiate between adenoma and adenocarcinoma in SNADET lesions is required to select the most appropriate treatment. This review describes the current state of knowledge about preoperative endoscopic diagnosis of SNADETs, such as duodenal adenoma and duodenal adenocarcinoma. Newer endoscopic techniques, including magnifying endoscopy, may help to guide these diagnostics, but their additional advantages remain unclear, and further studies are required to clarify these issues.