[Exocrine meets neuroendocrine: mimickers of pancreatic neuroendocrine neoplasms].

Neuroendocrine neoplasms (NENs) originate from various epithelial or neuroectodermal tissues, can occur in any organ, including the pancreas, and are characterized by the expression of the neuroendocrine markers synaptophysin and chromogranin A. Pancreatic neuroendocrine tumors (PanNETs) are well-differentiated epithelial neoplasms with morphological and immunohistochemical features of neuroendocrine differentiation of low, intermediate, or high grade. Pancreatic neuroendocrine carcinomas (PanNECs) are clinically aggressive, high-grade (poorly differentiated) carcinomas with morphologic features suggesting neuroendocrine differentiation, a high proliferative rate (> 20 mitoses per 2 mm and Ki67 index > 20%), and immunohistochemical labeling for neuroendocrine markers.

Phenotyping of tumor-associated macrophages in colorectal cancer: Impact on single cell invasion (tumor budding) and clinicopathological outcome.

Tumor-associated macrophages (TAM) play a controversial role in epithelial-mesenchymal transition (EMT) and prognosis of colorectal cancer (CRC). In particular, the microlocalization, polarization and prognostic impact of TAM in the immediate environment of invading CRC cells has not yet been established. To address this clinically relevant question, intraepithelial (iCD68) and stromal macrophages (sCD68), M1-macrophages (iNOS), M2-macrophages (CD163), cytokeratin-positive cancer cells (tumor buds) and expression of the anti-phagocytic marker CD47 were investigated in primary tumors of 205 well-characterized CRC patients.

HOX D13 expression across 79 tumor tissue types.

HOX genes control normal development, primary cellular processes and are characterized by a unique genomic network organization. Locus D HOX genes play an important role in limb generation and mesenchymal condensation. Dysregulated HOXD13 expression has been detected in breast cancer, melanoma, cervical cancer and astrocytomas.

Glypican 3 expression in human nonneoplastic, preneoplastic, and neoplastic tissues: a tissue microarray analysis of 4,387 tissue samples.

Several studies have shown that glypican 3 (GPC3) could be a useful diagnostic marker for hepatocellular carcinoma (HCC) and for differentiating HCC from nonneoplastic and preneoplastic liver disease. To systematically investigate the epidemiology of GPC3 expression in the liver and in other organs and tissues, we used tissue microarray technology comprising 4,387 tissue samples from 139 tumor categories and 36 nonneoplastic and preneoplastic tissue types. The immunohistochemical expression of GPC3 was assessed semiquantitatively using a 10% cutoff score and was detected in 9.

Chromosomal instability in gastric mucosa-associated lymphoid tissue lymphomas: a fluorescent in situ hybridization study using a tissue microarray approach.

Extranodal marginal zone B-cell lymphomas (mucosa-associated lymphoid tissue [MALT] lymphomas) of the gastrointestinal tract have been known to have characteristic chromosomal aberrations including trisomies of chromosomes 3, 12, and 18. However, knowledge of the clinical significance of cytogenetic changes in MALT lymphomas is still limited. In the present study, the frequency of the numeric and structural aberrations of the chromosomes 1, 3, 12, 18 and X and of the MALT1 gene as well as their potential clinical significance were analyzed by using fluorescent in situ hybridization on a tissue microarray containing 257 tissue samples from 203 cases of surgically resected primary gastric lymphomas including 115 cases of MALT lymphomas, 88 cases of diffuse large B-cell lymphomas (DLBCLs, 75 with an associated MALT lymphoma, so-called ex-MALT DLBCL, and 13 de novo), and 54 controls cases of Helicobacter pylori-associated chronic gastritis.