Histiocytic sarcoma with secondary involvement of the skin and expression of CD1a: evidence of indeterminate cell differentiation?

Background: Histiocytic sarcoma is an exceedingly rare malignant neoplasm composed of cells with a monocyte/macrophage phenotype. In the current nosology of histiocytic neoplasms, histiocytic sarcoma is separate from indeterminate cell histiocytosis, a generally benign disorder characterized by proliferation of a CD1a+ and S-100+ population of cells lacking Birbeck granules usually limited to the skin.

Methods: We present a case of histiocytic sarcoma in a 64-year-old man presenting as a peritonsillar mass and secondarily involving the skin.

Microarray analyses and molecular profiling of Stat3 signaling pathway induced by hepatitis C virus core protein in human hepatocytes.

Hepatitis C virus (HCV) infection is a major contributor to the development of end-stage liver disease, including cirrhosis and hepatocellular carcinoma (HCC). We have previously shown that HCV core protein promotes immortalization of primary human hepatocytes. To identify molecular changes involved in core protein-mediated immortalization, we have investigated differential gene expression by microarray analyses in primary human hepatocytes and HCV core gene introduced hepatocytes after senescence (early passage), immortalization (middle passage), and anchor-independent growth (late passage).

Acute promyelocytic leukemia and HIV-1 infection: case report and review of the literature.

We report a 27-year-old man with HIV-1 infection who developed acute promyelocytic leukemia (APL) with a novel complex three-way chromosomal translocation t(15;16;17). Induction of remission and consolidation with all-trans-retinoic acid (ATRA)- and anthracycline-based chemotherapy was followed by maintenance therapy consisting of ATRA, 6-mercaptopurine (6-MP), and methotrexate (MTX). Highly active antiretroviral therapy (HAART) was continued with brief interruptions.

Lymphoblastic Leukemia With Mature B-Cell Phenotype in Infancy.

Lymphoblastic leukemias with surface immunoglobulin light chain expression and L1/L2 blast morphology (French-American-British Classification) are rare. The poor prognosis of lymphoblastic leukemia in children under 1 year of age is attributed largely to rearrangements involving the mixed lineage leukemia (mll, also known as all1, htrx, trx1, or hrx) gene that occur with increased frequency in this population. Mll-rearranged cases with a mature B-cell phenotype are rare.

Lymphoblastic leukemia with mature B-cell phenotype in infancy.

Lymphoblastic leukemias with surface immunoglobulin light chain expression and L1/L2 blast morphology (French-American-British Classification) are rare. The poor prognosis of lymphoblastic leukemia in children under 1 year of age is attributed largely to rearrangements involving the mixed lineage leukemia (mll, also known as all1, htrx, trx1, or hrx) gene that occur with increased frequency in this population. Mll-rearranged cases with a mature B-cell phenotype are rare.

Diagnosis of cervical thymoma by fine needle aspiration biopsy with flow cytometry. A case report.

Background: Cervical thymoma is a rare entity. To our knowledge, this is the 20th reported case of cervical thymoma and the fourth case of fine needle aspiration biopsy (FNAB) of this entity. To our knowledge, this is the only case in which cervical thymoma was a diagnostic consideration at the time of the FNAB diagnosis.

Fine needle aspiration biopsy of a posttransplant lymphoproliferative disorder with pronounced plasmacytic differentiation presenting in the face. A case report.

Background: Posttransplant lymphoproliferative disorders (PTLDs) occur in fewer than 2% of transplant patients. However, as a group, 54% of PTLD patients die of these diseases. Presentation as only skin/superficial soft tissue nodules is rare, with this the second such reported case, and this is the only fine needle aspiration biopsy (FNAB) of such a case as well as the only FNAB of a plasmacytoid monomorphous/monoclonal PTLD.

Extranodal posttransplant plasmacytic hyperplasia with subsequent posttransplant plasmacytic malignancy: six-year interval case report and review of the literature.

Posttransplant lymphoproliferative disorders (PTLDs) represent a morphologic, immunophenotypic, and genotypic spectrum of disease. Most recently, Knowles et al divided PTLDs into 3 distinct categories: (1) plasmacytic hyperplasia, (2) polymorphic B-cell hyperplasia and polymorphic B-cell lymphoma, and (3) immunoblastic lymphoma and multiple myeloma. Although one form of PTLD may progress to another form, only 1 previous case has been reported in which multiple myeloma developed 14 months after an original diagnosis of plasmacytic hyperplasia.

Effective management of hepatitis C molecular testing improves test use without compromising patient management.

Context: The availability of effective antiviral therapy for hepatitis C has increased the need for molecular detection and quantification of circulating hepatitis C viral particles. The limits of detection differ for the quantitative and qualitative reverse transcriptase polymerase chain reaction (RT-PCR) assays; furthermore, adequate patient assessment requires both detection of hepatitis C virus when it is present and quantitation of the viral load when possible. The combination of these factors promotes the simultaneous ordering of both tests with the possibility of generating redundant test information.

Flow cytometric immunophenotyping in posttransplant lymphoproliferative disorders.

We studied the flow cytometric immunophenotyping (FCI) and genotypic data of 11 specimens from 10 transplant recipients and categorized them based on a scheme for posttransplant lymphoproliferative disorders (PTLDs). Specimens had been analyzed by polymerase chain reaction and/or Southern blot for T-cell and B-cell (immunoglobulin heavy chain and light chain genes) gene rearrangements (BGR). The categories for PTLDs were as follows: 1, 1; 2, 6; and 3, 4.