Guidelines on the histopathology of chronic pancreatitis. Recommendations from the working group for the international consensus guidelines for chronic pancreatitis in collaboration with the International Association of Pancreatology, the American Pancreatic Association, the Japan Pancreas Society, and the European Pancreatic Club.

Background: Chronic pancreatitis is a complex multifactorial fibro-inflammatory disease. Consensus guidelines are needed for the histopathological evaluation of non-autoimmune chronic pancreatitis (CP).

Methods: An international working group with experts on the histopathology of CP evaluated 15 statements generated from evidence on seven key clinically relevant questions.

Dynamic morphologic change and differentiation from fetal to mature pancreatic acinar cells in rats.

Background/aims: Because of the notion that pancreatic and duodenal homeobox 1 (PdX-1)-positive cells are pancreatic stem cells that contribute to the differentiation and proliferation of exocrine cells, we examined PdX-1-associated changes in the morphology of rat pancreatic acinar cells that occur between the late fetal and early neonatal periods.

Methods: Light and electron microscopy and PdX-1 and MIB-5 immunohistochemistry were used to examine pancreatic tissues obtained from fetal rats 22 days postconception (dpc), from newborn rats 48 and 72 hours after natural birth, and from rats 7 days after natural birth.

Results: At 22 dpc, the cytoplasm of the acinar cells was large and eosinophilic due to accumulation of dense and numerous zymogen granules.

Diagnostic challenge: intraductal neoplasms of the pancreatobiliary system.

To help pathologists avoid misdiagnosis of intraductal neoplasms arising from the pancreatobiliary system, we report two cases that illustrate diagnostic pitfalls. The first is of a 66-year-old man who complained of appetite loss. An early examination led to a diagnosis of intraductal papillary mucinous neoplasm.

Immunohistochemical analysis of thymic carcinoma focusing on the possibility of molecular targeted and hormonal therapies.

Objective: Thymic carcinoma is a rare mediastinal malignant tumor, and in many patients, the tumor is detected in an inoperable advanced stage. Even when chemotherapy is administered to such patients, the patients show a poor response. We investigated new biomarkers of therapeutic molecular targets.

Gastric- and intestinal-type marker expression in invasive ductal adenocarcinoma of the pancreas.

Background: Although invasive ductal adenocarcinoma of the pancreas (PDAC) manifests as a relatively uniform histomorphological feature of the pancreatobiliary type, it may be complicated by metaplastic changes and heterogeneous gastric and intestinal elements. This study aimed to investigate the complication rate and clinicopathological significance of such heterogeneous elements.

Methods: Fifty-nine patients who underwent resection of PDAC were examined in this study.

Autopsy cases of fulminant bacterial infection in adults: clinical onset depends on the virulence of bacteria and patient immune status.

To assist physicians in recognizing the potentially fatal onset of symptoms in cases of fulminant bacterial infection, we analyzed 11 autopsy cases of such infection (four caused by Streptococcus pneumoniae, four by S. pyogenes, one by S. dysgalactiae subsp.

Autopsy cases of miliary tuberculosis: clinicopathologic features including background factors.

To assist physicians, especially young physicians, in identifying tuberculosis (TB) infection before the terminal stage, we analyzed 7 cases of numerous tuberculous granulomas in multiple organs and compared clinical and autopsy findings between cases. Patients ranged in age from 41 to 86 years at the time of death. The main chief complaint was fever of unknown origin (3 of 7 cases [43%]).

Exocrine Pancreatic Neoplasms of Nonductal Origin: Acinar Cell Carcinoma, Pancreatoblastoma, and Solid-Pseudopapillary Neoplasm.

This review describes the clinicopathologic characteristics, differential diagnosis, and biologic behavior of exocrine pancreatic tumors of predominantly nonductal differentiation: acinar cell carcinoma, pancreatoblastoma, and solid-pseudopapillary neoplasm. Patients usually present with a well-demarcated, large, soft, solitary mass with expansile, rather than infiltrative, growth pattern. Cystic change is common.

Prognostic relevance of morphological types of intraductal papillary mucinous neoplasms of the pancreas.

Objective: The clinicopathological significance of four morphological types of intraductal papillary mucinous neoplasms of the pancreas (IPMNs; gastric, intestinal, pancreatobiliary and oncocytic) was assessed.

Design: Retrospective multicentre analysis of 283 surgically resected IPMNs.

Results: Of the 283 IPMNs, 139 were of the gastric type, 101 were intestinal, 19 were pancreatobiliary and 24 were oncocytic.

Intra-ampullary papillary-tubular neoplasm (IAPN): characterization of tumoral intraepithelial neoplasia occurring within the ampulla: a clinicopathologic analysis of 82 cases.

Background: There has been no uniform terminology for systematic analysis of mass-forming preinvasive neoplasms (which we term tumoral intraepithelial neoplasia) that occur specifically within the ampulla. Here, we provide a detailed analysis of these neoplasms, which we propose to refer to as intra-ampullary papillary-tubular neoplasm (IAPN).

Materials And Methods: Three hundred and seventeen glandular neoplasms involving the ampulla were identified through a review of 1469 pancreatoduodenectomies and 11 ampullectomies.

Tumor budding as a strong prognostic indicator in invasive ampullary adenocarcinomas.

Prognostication of invasive ampullary adenocarcinomas (AACs) and their stratification into appropriate management categories have been highly challenging owing to a lack of well-established predictive parameters. In colorectal cancers, recent studies have shown that tumor budding confers a worse prognosis and correlates significantly with nodal metastasis and recurrence; however, this has not been evaluated in AAC.To investigate the prevalence, significance, and clinical correlations of tumor budding in AAC, 244 surgically resected, stringently defined, invasive AAC were analyzed for tumor budding---defined as the presence of more than or equal to 5 isolated single cancer cells or clusters composed of fewer than 5 cancer cells per field measuring 0.

Possible recruitment of peripheral blood CXCR3+ CD27+ CD19+ B cells to the liver of chronic hepatitis C patients.

It has been suggested that hepatitis C virus (HCV) infects not only hepatocytes but also immune cells, including B cells. HCV infection of B cells is the likely cause of B-cell dysregulation disorders such as mixed cryoglobulinemia, rheumatoid factor production, and B-cell lymphoproliferative disorders that may evolve into non-Hodgkin's lymphoma. To clarify the effects of chronic HCV infection on B-cell dynamics, peripheral B cells from chronic hepatitis C patients (CHC) were characterized.

Intraductal oncocytic papillary carcinoma of the pancreas showing numerous hyaline globules in the lumen.

Two cases of intraductal oncocytic papillary carcinoma (IOPC) treated surgically were analyzed on light microscopy and immunohistochemistry: that of a 61-year-old man and that of a 55-year-old man. There were no clinical symptoms in either case. Pancreatic abnormalities were discovered incidentally on CT.

The Relationships Between Loss of Standard CD44 Expression and Lymph Node, Liver Metastasis in T3 Colorectal Carcinoma.

Purpose: The aim of the present study was to evaluate the standard CD44 (CD44s) expression in colorectal cancer (CRC) with invasion to the subserosal layer (T3), its relationship with clinicopathological characteristics, and its potential metastatic significance.

Materials And Methods: CD44s expression was measured on immunohistochemistry in tumors from 65 patients with primary colorectal carcinomas. CD44s expression was estimated at the deepest invaded area of the tumor in subserosal layer.

Sudden death caused by fulminant bacterial infection: background and pathogenesis of Japanese adult cases.

Objective: To analyze a risk factor for the onset of fulminant bacterial infection.

Patients And Methods: Nine unexpected acute death cases were clinicopathologically analysed. All cases represented the sudden onset of shock symptom, led to acute death within a few days, and later bacteremia was identified.

Ductal adenocarcinoma of the pancreas with psammomatous calcification. Report of a case.

Context: Calcification is extremely rare in pancreatic ductal adenocarcinomas, but we may sometimes encounter focal dystrophic calcification.

Case Report: We herein report the case of an 83-year-old female with pancreatic ductal adenocarcinoma associated with diffuse psammomatous calcification. The calcification was preoperatively detected by computed tomography.

Autopsy cases of fulminant-type bacterial infection with necrotizing fasciitis: group A (beta) hemolytic Streptococcus pyogenes versus Vibrio vulnificus infection.

Two autopsy cases of fulminant-type infection associated with necrotizing fasciitis were analyzed clinicopathologically. Both cases involved 57-year-old alcohol abusers. The former was a woman with group A (beta) hemolytic Streptococcus pyogenes infection, and the latter was a man with Vibrio vulnificus infection.

Expression of the tumor suppressor gene maspin and its significance in intraductal papillary mucinous neoplasms of the pancreas.

Background: Maspin is a member of the serpin family of protease inhibitors and is thought to inhibit carcinoma invasion, metastasis, and angiogenesis and induce apoptosis. We examined maspin expression immunohistochemically and assessed its significance in intraductal papillary mucinous neoplasm (IPMN) of the pancreas.

Methods: We examined 39 surgically resected specimens of IPMN that included 17 adenomas (IPMAs), 5 borderline tumors (IPMBs), 4 non-invasive carcinomas (non-invasive IPMCs), and 13 invasive carcinomas (invasive IPMCs).

Clinicopathological findings in fulminant-type pneumococcal infection: report of three autopsy cases.

Reported herein are three autopsy cases of fulminant-type pneumococcal sepsis with disseminated intravascular coagulation (DIC) resulting in death within a few days of onset of symptoms. Two of the three patients had previously had a splenectomy because of a hematological disorder. None of the patients had received pneumococcal vaccination.

Immunohistochemical analysis of nestin and c-kit and their significance in pancreatic tumors.

The purpose of the present study was to clarify the difference of expression of two stem cell markers, nestin and c-kit, among various pancreatic epithelial tumors and evaluate their utility. Immunohistochemistry was done for 99 surgically resected pancreatic tumor specimens, including 20 ductal adenocarcinoma (DAC), two undifferentiated carcinomas (UC), 31 intraductal papillary-mucinous neoplasms (IPMN), six mucinous cystic neoplasms (MCN), five serous cystadenomas (SCA), six acinar cell carcinomas, two pancreatoblastoma (PB), eight solid-pseudopapillary neoplasms (SPN), and 19 endocrine neoplasms (EN). Nestin was widely expressed in four SPN, one PB, one SCA, sarcoma areas in two UC, one MCN, and one DAC, and an area of oncocytic component in one IPMN.

Autoimmune pancreatitis: histo- and immunopathological features.

In recent years autoimmune pancreatitis (AIP) has been established as a special type of chronic pancreatitis. It is characterized by its histopathological and immunological features. The morphological hallmarks are periductal infiltration by lymphocytes and plasma cells, granulocytic epithelial lesions with focal destruction of the duct epithelium, venulitis, and diffuse sclerosis in advanced stages.