1,061 research outputs found
Systemic mastocytosis with associated myeloproliferative disease and precursor B lymphoblastic leukaemia with t(13;13)(q12;q22) involving FLT3.
Systemic mastocytoses represent neoplastic proliferations
of mast cells. In about 20% of cases systemic
mastocytoses are accompanied by clonal haematopoietic
non-mast cell-lineage disorders, most commonly myeloid
neoplasms. A case of systemic mastocytosis carrying the
characteristic mutation at codon 816 (D816V) in the KIT
gene of mast cells, with two concurrent accompanying
clonal haematopoietic non-mast cell-lineage disorders,
chronic myeloproliferative disease, unclassifiable and
precursor B lymphoblastic leukaemia is documented. Both
accompanying clonal haematopoietic non-mast cell-lineage
disorders carried the wild-type KIT gene, but had a
novel t(13;13)(q12;q22) involving the FLT3 locus at
13q12. The chronic myeloproliferative disease, unclassifiable
and the precursor B lymphoblastic leukaemia were
cured by syngenous stem cell transplantation, but the
systemic mastocytosis persisted for more than 10 years.
The additional impact of molecular techniques on the
correct diagnosis in haematological malignancies is
highlighted, and evidence is provided that, apart from
internal tandem duplications and mutations, FLT3 can be
activated by translocations
Indolent lymphoma: the pathologist's viewpoint
Indolent lymphomas have recently been the object of numerous studies, which have focused on new aspects relevant both for the better comprehension of their histogenesis and the identification of new therapeutic strategies. As marginal-zone lymphoma (MZL) represents the category of indolent lymphomas that has obtained more benefit from such an approach, the authors focused on the most recent achievements and not yet solved controversies in this area. In spite of their postulated common derivation, the three categories of MZL of the WHO Classification appear dissimilar. In fact, they show significant molecular differences among them as well as a certain heterogeneity within each group. By no means, there is a cogent need of more refined tools to revise these neoplasms and to produce a more rational grouping. The recent identification of the IRTA gene family corresponding to IG-like receptors differentially expressed in B-cells might contribute to their better understandin
Meningotheliomatöses Meningeom in einem reifen zystischen Teratom des Ovars
Zusammenfassung: Reife Teratome des Ovars zählen zu den Keimzelltumoren. Sie machen 27-44% aller Neoplasien des Ovars und bis zu 58% der benignen Ovarialtumoren aus. In reifen und unreifen Teratomen können sich sekundäre Tumoren der 3Keimblätter entwickeln. Diese können sowohl benigne als auch maligne sein. Wir berichten über den Fall eines meningotheliomatösen Meningeoms als Anteil eines reifen zystischen Teratoms bei einer 32-jährigen Patientin. Die typische Histomorphologie und die immunhistochemisch nachweisbare Expression von epithelialem Membranantigen (EMA) und Desmoplakin sind diagnostisch wegweisen
Rare KIT (CD117) expression in multiple myeloma abrogates the usefulness of imatinib mesylate treatment
Background: Imatinib mesylate blocks the tyrosine kinase activity of KIT (CD117) and is an effective treatment for gastrointestinal stromal tumors. In multiple myeloma, KIT expression has been detected by flow cytometry in about 33% of specimens, but no previous immunohistochemical assessment has yet been made of the expression pattern of KIT. Materials and methods: We performed immunohistochemical analyses of 100 patients, including 72 with multiple myeloma (MM), 8 with lymphoplasmacytic lymphoma (LPL), 10 with monoclonal gammopathy of undetermined significance (MGUS) and 10 with reactive plasmocytosis. One KIT-positive MM was sequenced using polymerase chain reaction analysis. Results: In MM, only 2 cases (2.8%) were KIT positive. The great majority of the cases (97, 2%) did not express the KIT receptor tyrosine kinase. No mutation of the c-kit gene was detected. Conclusions: KIT expression is a rare event in MM and not detectable in MGUS and LPL. Therefore, treatment with imatinib is unlikely to be effective in these patient
Indolent lymphoma: the pathologist's viewpoint
Abstract
Indolent lymphomas have recently been the object of numerous studies, which have focused on new aspects relevant both for the better comprehension of their histogenesis and the identification of new therapeutic strategies. As marginal-zone lymphoma (MZL) represents the category of indolent lymphomas that has obtained more benefit from such an approach, the authors focused on the most recent achievements and not yet solved controversies in this area. In spite of their postulated common derivation, the three categories of MZL of the WHO Classification appear dissimilar. In fact, they show significant molecular differences among them as well as a certain heterogeneity within each group. By no means, there is a cogent need of more refined tools to revise these neoplasms and to produce a more rational grouping. The recent identification of the IRTA gene family corresponding to IG-like receptors differentially expressed in B-cells might contribute to their better understanding
Selective transmission through very deep zero-order metallic gratings at microwave frequencies
Copyright © 2000 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Applied Physics Letters 77 (2000) and may be found at http://link.aip.org/link/?APPLAB/77/2789/1Zero-order metal grating structures are found to give extraordinary selective transmission at microwave frequencies through the resonant excitation of coupled surface waves. The metal slat structures with dielectric spacings as small as 250 µm strongly transmit wavelengths of several millimeters. A simple interpretation of these novel results which treats the deep grating structures as "filled" Fabry–Perot cavity systems gives model transmissivities which agree very well with the experimental data
A new diagnostic algorithm for Burkitt and diffuse large B-cell lymphomas based on the expression of CSE1L and STAT3 and on MYC rearrangement predicts outcome
Background Aggressive mature B-cell non-Hodgkin's lymphomas (BCL) sharing features of Burkitt's lymphoma (BL) and diffuse large B-cell lymphoma (DLBCL) (intermediate BL/DLBCL) but deviating with respect to one or more characteristics are increasingly recognized. The limited knowledge about these biologically heterogeneous lymphomas hampers their assignment to a known entity, raising incertitude about optimal treatment approaches. We therefore searched for discriminative, prognostic, and predictive factors for their better characterization. Patients and methods We analyzed 242 cytogenetically defined aggressive mature BCL for differential protein expression. Marker selection was based on recent gene-expression profile studies. Predictive models for diagnosis were established and validated by a different set of lymphomas. Results CSE1L- and inhibitor of DNA binding-3 (ID3)-overexpression was associated with the diagnosis of BL and signal transduction and transcription-3 (STAT3) with DLBCL (P<0.001 for all markers). All three markers were associated with patient outcome in DLBCL. A new algorithm discriminating BL from DLBCL emerged, including the expression of CSE1L, STAT3, and MYC translocation. This ‘new classifier' enabled the identification of patients with intermediate BL/DLBCL who benefited from intensive chemotherapy regimens. Conclusion The proposed algorithm, which is based on markers with reliable staining properties for routine diagnostics, represents a novel valid tool in separating BL from DLBCL. Most interestingly, it allows segregating intermediate BL/DLBCL into groups with different treatment requirement
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