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Pittsburgh, PA, United States

Gibson S.E.,University of Pittsburgh | Swerdlow S.H.,University of Pittsburgh | Craig F.E.,University of Pittsburgh | Surti U.,University of Pittsburgh | And 6 more authors.
American Journal of Surgical Pathology | Year: 2011

The 2008 World Health Organization Classification of Tumours of Haematopoietic and Lymphoid Tissues defines monomorphic posttransplant lymphoproliferative disorders (M-PTLDs) as lymphoid or plasmacytic proliferations that fulfill the criteria for one of the B-cell or T/NK-cell neoplasms recognized in immunocompetent patients. However, indolent B-cell lymphomas, such as extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma), are specifically excluded from this category. In this study, we describe the clinicopathologic features of 4 posttransplant lymphoma-like proliferations that were Epstein-Barr virus (EBV) positive, but were otherwise completely typical for a MALT lymphoma. The 4 patients (age, 12 to 71 y) had received solid organ transplants (2 hearts, 1 kidney, 1 kidney/pancreas) at a median of 116 months before presentation, and had been maintained on varying immunosuppressive regimens that included cyclosporine, azathioprine, tacrolimus, and sirolimus. Three of the 4 patients presented with solitary subcutaneous masses, whereas the fourth patient presented with a solitary orbital soft tissue mass. All the 4 cases were morphologically typical for MALT lymphoma, demonstrated plasmacytic differentiation with IgA heavy chain restriction (3 cases κ positive, 1 case λ positive), and were diffusely EBV-encoded small RNA positive. Patients were followed for a median of 44.9 months, and all achieved a complete response following various regimens that included reduced immunosuppression with or without antiviral therapy, local surgical excision, rituximab, or local radiation therapy. The uniform EBV positivity and response to immune reconstitution in some cases suggest that EBV-positive MALT lymphomas arising in the posttransplant setting should be included among PTLDs. Whether their distinctive subcutaneous/soft tissue localization and IgA positivity are uniform features will require identification of additional cases. Copyright © 2011 by Lippincott Williams & Wilkins. Source

Gradowski J.F.,University of Pittsburgh | Jaffe E.S.,U.S. National Cancer Institute | Warnke R.A.,Stanford University | Pittaluga S.,U.S. National Cancer Institute | And 3 more authors.
Modern Pathology | Year: 2010

Follicular lymphomas with plasmacytic differentiation were described more than two decades ago. However, the possibility that some of these reported cases are marginal zone lymphomas or composite lymphomas must be considered. In addition, it is also uncertain whether follicular lymphomas with plasmacytic differentiation have any unique cytogenetic or other features. Therefore, fluorescence immunophenotypic and interphase cytogenetic analysis of 14 well-characterized follicular lymphomas with plasmacytic differentiation was performed using a CD138 antibody to identify the plasma cells and with BCL2, BCL6, IGH@ and MALT1 break-apart probes and a chromosome 12 centromeric probe. CD10 was expressed in 12/14 cases, BCL6 in 12/12 cases and BCL2 in 12/14 cases. At least one cytogenetic abnormality was identified in 12/14 cases. The same abnormality was present in both the plasmacytic (CD138) and non-plasmacytic (CD138) component in all 10 evaluable cases. BCL2 rearrangements were present in seven cases (5 IGH@ rearranged, 1 IGH@-not rearranged, 1 IGH@-not evaluable), BCL6 rearrangement in two (1 also with BCL2/IGH@ rearrangement), 12 in 1, MALT1 without 18 in 1, IGH@ rearrangement without other abnormalities in 1 and IGH@ rearranged or partially deleted in 1 case. No cases showed BCL6 (3q27) or a MALT1 rearrangement. All six cases with an isolated BCL2 rearrangement had predominantly interfollicular plasmacytic cells whereas, 6/7 cases without the translocation had concentrations of intrafollicular or perifollicular plasmacytic cells (P0.005), as did the case with BCL2 and BCL6 translocations. These results support the existence of bona fide follicular lymphomas with plasmacytic differentiation and support the clonal relationship of the neoplastic lymphoid and plasma cells in at least most of these cases. The differential distribution of the plasma cells, specifically in relation to the presence or absence of an isolated BCL2 rearrangement suggests that the latter cases may be distinctive, sharing some features with marginal zone lymphomas. © 2010 USCAP, Inc. All rights reserved. Source

Craig F.E.,University of Pittsburgh | Monaghan S.A.,University of Pittsburgh | Surti U.,Pittsburgh Cytogenetics Laboratory | Swerdlow S.H.,University of Pittsburgh
Cytometry Part B - Clinical Cytometry | Year: 2012

Background: Flow cytometric immunophenotyping has an established role in the diagnosis and monitoring of B-lymphoblastic leukemia (B-LL). However, the search continues for an optimal reagent set that can identify leukemic blasts with specificity, reproducibility, and sensitivity, at any point during the course of the disease and in every specimen type. Methods: This study evaluated the diagnostic utility of detecting the intracytoplasmic antigens zeta-associated protein (ZAP-70) and Bcl-2 in the distinction between the leukemic blasts of B-LL and hematogones. Results: In comparison with hematogones in reference specimens, significantly higher levels of Bcl-2 were identified in 21 of 23 (91%) B-LL. In particular, Bcl-2 expression was consistently higher in leukemic blasts with bright intensity CD10 expression than the equivalent most immature (CD10 bright intensity) hematogones. As previously reported, Bcl-2 expression was lower in B-LL with BCR-ABL1 gene rearrangement, but the fluorescence intensity of this group of specimens was still significantly higher than that seen for hematogones. In contrast, ZAP-70 was expressed at significantly higher levels in only 7 of 23 (30%) B-LL and demonstrated other findings that might limit clinical utility, including differences in the level of ZAP-70 expression during therapy and between blasts in the peripheral blood and bone marrow. Conclusions: Bcl-2 over-expression provides a useful tool for the distinction between B-LL and hematogones. In contrast, although further optimization of the ZAP-70 assay might increase the sensitivity of detection, over-expression of ZAP-70 was identified in only a minority of B-LL. © 2011 International Clinical Cytometry Society. Source

Gibson S.E.,University of Pittsburgh | Swerdlow S.H.,University of Pittsburgh | Ferry J.A.,Massachusetts General Hospital | Surti U.,University of Pittsburgh | And 4 more authors.
Haematologica | Year: 2011

Background In the 2008 World Health Organization classification, small lymphocytic lymphoma is defined as a neoplasm with the tissue morphology and immunophenotype of chronic lymphocytic leukemia, but with absence of leukemia. Minimal criteria of tissue involvement to separate small lymphocytic lymphoma from monoclonal B-cell lymphocytosis have not been defined. Design and Methods We reviewed the clinicopathological features of 36 patients with extramedullary tissue biopsies containing chronic lymphocytic leukemia-type cells and less than 5×10 9/L peripheral blood monoclonal B cells. Pathological features (extent and patterns of involvement, architectural preservation, presence of proliferation centers) as well as cytogenetic and radiological findings were examined in relation to clinical outcome. Results The biopsies were performed to evaluate lymphadenopathy in 20 patients and for other reasons (most frequently staging of a non-hematologic neoplasm) in 16 patients. At latest followup (median 23 months), 21 untreated patients had no or stable lymphadenopathy, 3 had regressed lymphadenopathy, and 12 had developed progressive lymphadenopathy and/or received therapy for chronic lymphocytic leukemia/small lymphocytic lymphoma. Features associated with progression/treatment included lymph nodes 1.5 cm or greater on imaging studies (P=0.01) and presence of proliferation centers in the biopsied tissue (P=0.004). Neither the size nor extent of involvement of the excised lymph node correlated with progression/treatment. Conclusions Our findings suggest that biopsies containing chronic lymphocytic leukemia-type cells, but lacking proliferation centers and with non-enlarged or only slightly enlarged lymph nodes on imaging, represent a very indolent disease that may best be considered a tissue equivalent of monoclonal B-cell lymphocytosis rather than overt small lymphocytic lymphoma. We propose that such cases be designated as tissue involvement by chronic lymphocytic leukemia/small lymphocytic lymphoma-like cells of uncertain significance. © 2011 Ferrata Storti Foundation. Source

Dobrowolski S.F.,Childrens Hospital of Pittsburgh | Lyons-Weiler J.,University of Pittsburgh | Spridik K.,Childrens Hospital of Pittsburgh | Biery A.,Childrens Hospital of Pittsburgh | And 4 more authors.
Molecular Genetics and Metabolism | Year: 2015

While phenylalanine (PHE) is the toxic insult in phenylketonuria (PKU), mechanisms underlying PHE toxicity remain ill-defined. Altered DNA methylation in response to toxic exposures is well-recognized. DNA methylation patterns were assessed in blood and brain from PKU patients to determine if PHE toxicity impacts methylation. Methylome assessment, utilizing methylated DNA immunoprecipitation and paired-end sequencing, was performed in DNA obtained from brain tissue of classical PKU patients, leukocytes from poorly controlled PKU patients, leukocytes from well controlled PKU patients, and appropriate control tissues. In PKU brain tissue, expression analysis determined the impact of methylation on gene function. Differential methylation was observed in brain tissue of PKU patients and expression studies identified downstream impact on gene expression. Altered patterns of methylation were observed in leukocytes of well controlled and poorly controlled patients with more extensive methylation in patients with high PHE exposure. Differential methylation of noncoding RNA genes was extensive in patients with high PHE exposure but minimal in well controlled patients. Methylome repatterning leading to altered gene expression was present in brain tissue of PKU patients, suggesting a role in neuropathology. Aberrant methylation is observed in leukocytes of PKU patients and is influenced by PHE exposure. DNA methylation may provide a biomarker relating to historic PHE exposure. © 2015 Elsevier Inc. Source

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