Günter Klöppel

Consensus statement on the pathology of IgG4-related disease.

IgG4-related disease is a newly recognized fibro-inflammatory condition characterized by several features: a tendency to form tumefactive lesions in multiple sites; a characteristic histopathological appearance; and—often but not always—elevated serum IgG4 concentrations. An international symposium on IgG4-related disease was held in Boston, MA, on 4–7 October 2011. The organizing committee comprising 35 IgG4-related disease experts from Japan, Korea, Hong Kong, the United Kingdom, Germany, Italy, Holland, Canada, and the United States, including the clinicians, pathologists, radiologists, and basic scientists. This group represents broad subspecialty expertise in pathology, rheumatology, gastroenterology, allergy, immunology, nephrology, pulmonary medicine, oncology, ophthalmology, and surgery. The histopathology of IgG4-related disease was a specific focus of the international symposium. The primary purpose of this statement is to provide practicing pathologists with a set of guidelines for the diagnosis of IgG4-related disease. The diagnosis of IgG4-related disease rests on the combined presence of the characteristic histopathological appearance and increased numbers of IgG4+ plasma cells. The critical histopathological features are a dense lymphoplasmacytic infiltrate, a storiform pattern of fibrosis, and obliterative phlebitis. We propose a terminology scheme for the diagnosis of IgG4-related disease that is based primarily on the morphological appearance on biopsy. Tissue IgG4 counts and IgG4:IgG ratios are secondary in importance. The guidelines proposed in this statement do not supplant careful clinicopathological correlation and sound clinical judgment. As the spectrum of this disease continues to expand, we advocate the use of strict criteria for accepting newly proposed entities or sites as components of the IgG4-related disease spectrum.

International Consensus Diagnostic Criteria for Autoimmune Pancreatitis: Guidelines of the International Association of Pancreatology

Objectives: To achieve the goal of developing international consensus diagnostic criteria (ICDC) for autoimmune pancreatitis (AIP). Methods: An international panel of experts met during the 14th Congress of the International Association of Pancreatology held in Fukuoka, Japan, from July 11 through 13, 2010. The proposed criteria represent a consensus opinion of the working group. Results: Autoimmune pancreatitis was classified into types 1 and 2. The ICDC used 5 cardinal features of AIP, namely, imaging of pancreatic parenchyma and duct, serology, other organ involvement, pancreatic histology, and an optional criterion of response to steroid therapy. Each feature was categorized as level 1 and 2 findings depending on the diagnostic reliability. The diagnosis of type 1 and type 2 AIP can be definitive or probable, and in some cases, the distinction between the subtypes may not be possible (AIP-not otherwise specified). Conclusions: The ICDC for AIP were developed based on the agreement of an international panel of experts in the hope that they will promote worldwide recognition of AIP. The categorization of AIP into types 1 and 2 should be helpful for further clarification of the clinical features, pathogenesis, and natural history of these diseases.

Stat3/Socs3 Activation by IL-6 Transsignaling Promotes Progression of Pancreatic Intraepithelial Neoplasia and Development of Pancreatic Cancer

Physiological levels of Kras(G12D) are sufficient to induce pancreatic intraepithelial neoplasias (PanINs); the mechanisms that drive PanIN progression are unknown. Here, we establish that, in addition to oncogenic Kras(G12D), IL-6 transsignaling-dependent activation of Stat3/Socs3 is required to promote PanIN progression and pancreatic ductal adenocarcinoma (PDAC). Myeloid compartment induces Stat3 activation by secreting IL-6; consequently, IL-6 transsignaling activates Stat3 in the pancreas. Using genetic tools, we show that inactivation of IL-6 transsignaling or Stat3 inhibits PanIN progression and reduces the development of PDAC. Aberrant activation of Stat3 through homozygous deletion of Socs3 in the pancreas accelerates PanIN progression and PDAC development. Our data describe the involvement of IL-6 transsignaling/Stat3/Socs3 in PanIN progression and PDAC development.

Recommendations for the nomenclature of IgG4-related disease and its individual organ system manifestations

John H. Stone, Arezou Khosroshahi, Vikram Deshpande, John K. C. Chan, J. Godfrey Heathcote, Rob Aalberse, Atsushi Azumi, Donald B. Bloch, William R. Brugge, Mollie N. Carruthers, Wah Cheuk, Lynn Cornell, Carlos Fernandez-Del Castillo, Judith A. Ferry, David Forcione, Gunter Kloppel, Daniel L. Hamilos, Terumi Kamisawa, Satomi Kasashima, Shigeyuki Kawa, Mitsuhiro Kawano, Yasufumi Masaki, Kenji Notohara, Kazuichi Okazaki, Ji Kon Ryu, Takako Saeki, Dushyant Sahani, Yasuharu Sato, Thomas Smyrk, James R. Stone, Masayuki Takahira, Hisanori Umehara, George Webster, Motohisa Yamamoto, Eunhee Yi, Tadashi Yoshino, Giuseppe Zamboni, Yoh Zen, and Suresh Chari

ENETS Consensus Guidelines for the Management of Patients with Digestive Neuroendocrine Neoplasms of the Digestive System: Well-Differentiated Pancreatic Non-Functioning Tumors

ENETS Consensus Guidelines for the Management of Patients with Digestive Neuroendocrine Neoplasms of the Digestive System : Well-Differentiated Pancreatic Non-Functioning Tumors

StellaTUM: current consensus and discussion on pancreatic stellate cell research

The field of pancreatic stellate cell (PSC) biology is very young, as the essential in-vitro tools to study these cells (ie, methods to isolate and culture PSC) were only developed as recently as in 1998. Nonetheless, there has been an exponential increase in research output in this field over the past decade, with numerous research groups around the world focusing their energies into elucidating the biology and function of these cells. It is now well established that PSC are responsible for producing the stromal reaction (fibrosis) of two major diseases of the pancreas—chronic pancreatitis and pancreatic cancer. Despite exponentially increasing data, the methods for studying PSC remain variable. Although within individual laboratories methods are consistent, different methodologies used by various research groups make it difficult to compare results and conclusions. This article is not a review article on the functions of PSC. Instead, members of the Pancreatic Star Alliance (http://www.pancreaticstaralliance.com) discuss here and consolidate current knowledge, to outline and delineate areas of consensus or otherwise (eg, with regard to methodological approaches) and, more importantly, to identify essential directions for future research. Hepatic stellate cells (HSC) were first described by Karl von Kupffer in 1876; however, similar cells in the pancreas were first observed in the 1980s.1–3 In 1998, Apte et al 4 and Bachem et al 5 isolated and cultured PSC.4 5 In the normal pancreas, PSC are located in close proximity to the basal aspect of pancreatic acinar cells. In sections immunostained for the marker desmin (a cytoskeletal protein), quiescent PSC can be seen as cells with a central cell body and long cytoplasmic projections extending along the base of adjacent acinar cells similar to that of pericytes in the mammary gland. …

The mucin profile of noninvasive and invasive mucinous cystic neoplasms of the pancreas.

Recently, it was shown that ductal adenocarcinomas and intraductal papillary–mucinous neoplasms of the pancreas differ in their expression of the mucin markers MUC1 and MUC2 while both tumors express MUC5AC. It is not known whether mucinous cystic neoplasms of the pancreas have their own mucin profile. To clarify this issue, 22 mucinous cystic neoplasms were examined immunohistologically for their expression of MUC1, MUC2, MUC5AC, and MUC6 and also for the protein products of the tumor suppressor genes p53 and DPC4 and the mismatch repair genes. Noninvasive mucinous cystic neoplasms, regardless of the degree of cellular atypia, were all positive for MUC5AC and negative for MUC1, with the exception of the cyst-lining epithelium of a single case with eosinophilic cytology (case no. 16). Only in cases with an invasive component was MUC1 expression observed. MUC2 expression was restricted to goblet cells scattered within the epithelium of the mucinous cystic neoplasms and was often accompanied by endocrine cells, a further indication of intestinal differentiation. DPC4 expression was maintained in all tumors, except for three invasive carcinomas. p53 nuclear reactivity was found in one borderline tumor and four invasive mucinous cystic carcinomas. The results suggest that the epithelium of noninvasive mucinous cystic neoplasms does not differ in its expression of MUC5AC from ductal adenocarcinomas, intraductal papillary–mucinous neoplasms, and metaplastic pancreatic duct epithelium. The fact that noninvasive mucinous cystic neoplasms lack MUC1 expression (except for an eosinophilic variant) but express it when they become invasive might be used as a marker indicating the step of progression from noninvasiveness to invasiveness.

The ENETS and AJCC/UICC TNM classifications of the neuroendocrine tumors of the gastrointestinal tract and the pancreas: a statement

In 2006 a working group of the European Neuroendocrine Tumor Society (ENETS) developed and published a proposal for a TNM staging classification of the neuroendocrine tumors (NET) of the foregut (stomach, duodenum, and pancreas), accompanied by a grading system [1]. This was followed in 2007 by the publication of a TNM staging classification of the midgut and hindgut NETs (ileum, appendix, colon/rectum) from the same group [2]. These were the first TNM classifications to be developed for the NETs that took into account the distinctive growth patterns of these tumors and that differentiated these tumors from the other gastroenteropancreatic (GEP) carcinomas. These classification systems additionally supplemented the WHO classification of the GEP-NETs [3], some aspects of which had already been recognized as prognostically relevant [4]. In the years that followed the publication of these proposed TNM classifications, the classifications that concerned the foregut GEP-NETs and particularly the pancreatic NETs were validated by several studies, and their biological relevance and power to discriminate among prognostic groups was largely confirmed [5–9]. In 2009 the seventh edition of the AJCC/UICC TNM classification of the most important malignant tumors appeared [10]. It also includes new TNM staging classifications of the gastrointestinal carcinoids and of pancreatic neuroendocrine tumors, which had not previously been included in the AJCC/UICC staging classifications. However, the seventh edition of the AJCC/UICC TNM classification does not apply to high grade (large cell and small cell) neuroendocrine carcinomas and does not exactly follow the ENETS classifications for some of the anatomic sites. No data are presented to justify the use of different staging parameters. The result is that there now exist two parallel systems, each of which uses identical TNM terminology but may refer to different types and extents of disease for certain NETs. This discrepancy will lead to much confusion among clinicians and will likely limit the ability to compare research G. Kloppel Consultation Center for Pancreatic and Endocrine Tumors, Department of Pathology, Technical University of Munich, Munich, Germany

ENETS Consensus Guidelines Update for the Management of Patients with Functional Pancreatic Neuroendocrine Tumors and Non-Functional Pancreatic Neuroendocrine Tumors.

ENETS Consensus Guidelines Update for the Management of Patients with Functional Pancreatic Neuroendocrine Tumors and Non-Functional Pancreatic Neuroendocrine Tumors

ENETS consensus guidelines for the standards of care in neuroendocrine tumors: Somatostatin receptor imaging with IIIIn-pentetreotide

ENETS Consensus Guidelines for the Standards of Care in Neuroendocrine Tumors : Somatostatin Receptor Imaging with In-111-Pentetreotide