Search

The latest WHO classification of tumors of the digestive system (2019) has introduced new concepts for the stratification of intraductal neoplasms of the pancreas, mostly based on molecular genetics and malignant potential. Among them, pancreatic intraepithelial neoplasias (PanINs) and intraductal papillary mucinous neoplasms (IPMN) are both precursors of pancreatic ductal adenocarcinoma, whereas intraductal oncocytic papillary neoplasms (IOPN) and intraductal tubulopapillary neoplasms (ITPN) are usually associated with less aggressive subtypes of pancreatic cancer and therefore have a much better prognosis. Hence, it is of utmost importance to correctly classify these lesions and to distinguish them from each other as well as from other nonductal types of neoplasms, which can rarely display an intraductal growth, such as neuroendocrine tumors and acinar cell carcinomas. PanIN are microscopic lesions with limited clinical significance. In contrast, all other intraductal neoplasms can be identified as cystic processes and/or solid tumors by means of imaging, thereby setting an indication for a potential surgical resection. This review presents diagnostically relevant aspects of intraductal neoplasms of the pancreas, which are instrumental for the discussion within interdisciplinary tumor boards (resection vs. watch-and-wait strategies) as well as to determine the extent of resection intraoperatively., (© 2021. Springer Medizin Verlag GmbH, ein Teil von Springer Nature.)

Pancreatitis harbors a spectrum of different inflammatory changes of the pancreas of variable etiology and histopathology. In this context, common variants have to be distinguished from rare variants to optimize therapy. Each type of pancreatitis has characteristic features such as the age of patients and clinical presentation as well as the composition of the inflammatory infiltrates and histological changes., (© 2021. Springer Medizin Verlag GmbH, ein Teil von Springer Nature.)

Diagnostic radiology and diagnostic pathology are medical disciplines that use a variety of morphological analyses with different macroscopic and microscopic resolutions for diagnosis and staging of cancers. In the clinical setting, radiology and pathology departments are often spatially separated. However, there are examples of increasingly tight cooperation and convergence, for example in the setting of multidisciplinary tumor boards. This article focuses exemplarily on the correlations of radiological and histopathological diagnostics in pancreatic cancer., (© 2021. The Author(s).)

Background: Besides host defense against infections, the main function of the immune system is to eliminate tumor cells. Therefore, nearly, all solid tumors have a heterogeneous fibro-inflammatory microenvironment, which consists of myofibroblastic cells, extracellular matrix components, and infiltrates from various types of immune cell. In particular, pancreatic ductal adenocarcinoma is a prototype of a tumor with a pronounced inflammatory microenvironment, in which the majority of the tumor mass consists of nonneoplastic stromal and immune cells. Our own data and data from the literature indicate a protective role of tumor-infiltrating T cells for the host. On the other hand, we were able to show that a defined T cell subpopulation paradoxically promotes the progression of the tumor. Our investigations now focus on these cells, known as "Th17," in the tumor microenvironment., Objectives: To elucidate the mechanisms of the infiltrated immune cells and their mediators in the tumor microenvironment., Materials and Methods: Human pancreatic cancer tissue was used for (immune) histological staining and morphometric analysis and the results were correlated with clinical parameters and with diffusion-weighted magnetic resonance imaging images. The molecular mechanisms were analyzed in cell culture approaches using human tumor cells and human immune cells. With molecular biological methods and functional assays cell growth, invasion and colony formation were assessed. The in vivo correlation of the results and functional interventions were tested in murine and avian (xenograft) models., Results and Conclusion: Tumor-infiltrating immune cells of type Th17 and their mediators promoted the progression of the tumor depending on density, activation status, and cytokine profile. On molecular level, we identified a Th17-mediated increase of tumor cell migration and invasion, an increased neoangiogenesis, as well as a reorganization of the tumor stroma and microarchitecture. The data show that the progression of pancreatic cancer, depends on the status of activation and the cytokine profile of the infiltrated T cells.