Jeannine T. Holden

2006 Bethesda International Consensus recommendations on the flow cytometric immunophenotypic analysis of hematolymphoid neoplasia: Medical indications†

The clinical indications for diagnostic flow cytometry studies are an evolving consensus, as the knowledge of antigenic definition of hematolymphoid malignancies and the prognostic significance of antigen expression evolves. Additionally the standard of care is not routinely communicated to practicing clinicians and diagnostic services, especially as may relate to new technologies. Accordingly there is often uncertainty on the part of clinicians, payers of medical services, diagnostic physicians and scientists as to the appropriate use of diagnostic flow cytometry. In an attempt to communicate contemporary diagnostic utility of immunophenotypic flow cytometry in the diagnosis and follow‐up of patients with hematolymphoid malignancies, the Clinical Cytometry Society organized a two day meeting of international experts in this area to reach a consensus as to this diagnostic tool. This report summarizes the appropriate use of diagnostic flow cytometry as determined by unanimous approval of these experienced practitioners.

Ocular adnexal lymphoid proliferations: Clinical, histologic, flow cytometric, and molecular analysis of forty-three cases

PURPOSE To describe the clinical features, histologic findings, flow cytometric immunophenotypes, and molecular profiles of ocular adnexal lymphoid proliferations. STUDY DESIGN Prospective noncomparative case series. PARTICIPANTS Forty-three patients suspected of having ocular adnexal lymphoid proliferations were biopsied and prospectively evaluated. METHODS Provisional diagnoses were made on the basis of routine histology and immunohistochemistry for B and T cells. Results of flow cytometric immunophenotyping (FCI) and molecular assessment using polymerase chain reaction for immunoglobulin heavy chain (IgH) and TCR gamma chain gene rearrangement and bcl-2/IgH translocation were then incorporated into a final diagnosis. Demographic and clinical outcome data were collected. MAIN OUTCOME MEASURES Final diagnosis based on histology, flow cytometry, and polymerase chain reaction. RESULTS Forty-three cases were studied. Final diagnoses included 17 lymphomas, 18 chronic inflammations, 4 reactive lymphoid hyperplasias, and 4 atypical lymphoid infiltrates. Preliminary evaluation accurately categorized all 43 cases as either lymphoma or nonlymphoma. FCI permitted more precise subclassification of the lymphomas according to the Revised European American Lymphoma (REAL) system of nomenclature as follows: eight marginal zone B cell (mucosa-associated lymphoid tissue type), three mantle cell, two follicular, three large cell, and one lymphoplasmacytoid lymphoma. FCI showed a clonal B cell proliferation in 94% (16 of 17) of the lymphomas; FCI identified a clonal B cell population in 4% (1 of 25) of cases of nonlymphomas. Molecular evidence of clonality was identified in 88% (15 of 17) of lymphomas, 39% (7 of 18) of chronic inflammations, and 50% (4 of 8) of reactive lymphoid hyperplasias and atypical lymphoid infiltrates. CONCLUSIONS The histologic diagnosis of ocular adnexal lymphoid lesions is highly accurate when determined by an experienced pathologist. FCI refines the histologic diagnosis and classification. Results of molecular studies should be interpreted in conjunction with clinical, histologic, and immunophenotyping findings.

Immunophenotypic Analysis of Anaplastic Large Cell Lymphoma by Flow Cytometry

We studied the antigen expression profiles of 19 anaplastic large cell lymphoma (ALCL) cases by multiparameter flow cytometry. The neoplastic cells expressed CD45, HLA-DR, and CD30 in all cases. At least 1 T cell-associated antigen was expressed in each case (CD2, 12/17 [71%]; CD4, 12/19 [63%]; CD3, 6/19 [32%]; CD7, 6/19 [32%]; CD5, 5/19 [26%]; CD8, 4/19 [21%]). CD25 was expressed in 14 (88%) of 16 cases. CD13 was expressed unexpectedly in 8 (47%) of 17 cases. One CD13+ ALCL also was positive for CD33 and 2 others for CD15, CD19, CD20, CD22, CD14, and CD36 were not expressed. Anaplastic lymphoma kinase protein was detected in about 33% (3/9) of ALCLs examined by flow cytometric immunophenotyping (FCI); expression was validated by immunohistochemical analysis. Of 19 ALCL cases, 12 were diagnosed solely based on FCI findings in conjunction with morphologic evaluation of body fluid (1 case), fine-needle aspirate (3 cases), or excisional biopsy specimen (8 cases). The diagnoses of the remaining 7 cases were suggested strongly by FCI and confirmed by immunohistochemical analysis. FCI is useful to aid in diagnosis of ALCL, particularly along with fine-needle aspiration evaluation. ALCL with aberrant expression of myeloid antigens should not be mistaken for extramedullary myeloid tumor.

Inhibition of MAP Kinase Kinase Causes Morphological Reversion and Dissociation between Soft Agar Growth and in Vivo Tumorigenesis in Angiosarcoma Cells

Activated ras causes increased activity of several signal transduction systems, including the mitogen-activated protein kinase kinase (MAPKK) pathway and the phosphoinositol-3-kinase (PI-3-K) pathway. We have previously shown that the PI-3-K pathway plays a major role in regulation of ras-mediated tumor angiogenesis in angiosarcoma cells. However, the contribution of the MAPKK pathway to tumorigenesis and angiogenesis is not fully understood. Overexpression of constitutively active forms of MAPKK has previously been shown to transform nonmalignant NIH3T3 fibroblasts, but the effect of down-regulation of MAPKK on tumorigenesis and angiogenesis in a well established tumor has not been fully explored. We introduced a dominant negative MAPKK gene into SVR murine angiosarcoma cells. Introduction of a dominant negative MAPKK causes a significant decrease in proliferation rate in vitro and morphological reversion. Cells expressing the dominant negative MAPKK have a greatly decreased ability to form colonies in soft agar compared with wild-type cells. Despite the decreased cell growth in vitro and inability to grow in soft agar, the cells were equally tumorigenic in nude mice. Our results suggest that the MAPKK pathway is required for soft agar growth of angiosarcoma cells, and separates the phenotypes of soft agar growth versus in vivo tumorigenicity. These findings have implications in the development of signal transduction modulators as potential antineoplastic agents.

Flow cytometry in the differential diagnosis of lymphocyte-rich thymoma from precursor T-cell acute lymphoblastic leukemia/lymphoblastic lymphoma

We compared the antigen expression profile of thymocytes in lymphocyte-rich thymoma with that of precursor T-cell acute lymphoblastic leukemia/lymphoblastic lymphoma (T-cell ALL/LBL) cells using 4-colorflow cytometry. In all 15 thymoma cases, the thymocytes demonstrated 3 distinct subpopulations. The least mature cells (double-negative) expressed low-density CD2 and CD5, high-density CD7, CD10, CD34, and heterogeneous CD4 and CD8. They had the lowest density CD45 expression and were surface CD3-. The immature cells (double-positive) expressed CD2, CD5, CD7, CD4, CD8, heterogeneous surface CD3, and intermediate-density CD45. They were CD10- and CD34-. The mature cells (single-positive) expressed CD2, surface CD3, CD5, CD7, and CD4 or CD8. The heterogeneous expression of surface CD3, CD4, and CD8 also created a characteristic smearing pattern for these antigens. In all 15 T-cell ALL/LBL cases, the lymphoblasts formed a tight cluster without discrete subpopulations or smearing pattern. Of 5 double-negative cases, 4 demonstrated loss of CD2, CD10, or CD34 expression. Of 7 double-positive cases, 5 showed complete loss of surface CD3, CD2, and/or CD5; 4 were CD10+; and 2 were CD34+. Of 3 single-positive cases, 2 showed loss of CD2 and/or aberrant expression of CD34. Analysis of antigen expression pattern, the presence or absence of T cell-associated antigen deletion, and the expression of CD10 and CD34 by 4-color flow cytometry can help differentiate thymoma from T-cell ALL/LBL.

The effects of pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF) on platelet recovery in breast cancer patients undergoing autologous bone marrow transplantation

OBJECTIVE To assess the safety and efficacy of pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF) administered after autologous bone marrow transplantation (ABMT). PATIENTS AND METHODS Two randomized, double-blind, placebo-controlled studies were done. In the phase 1/2 study, 75 breast cancer patients underwent a bone marrow harvest and myeloablative STAMP V chemotherapy and were randomized to receive placebo or one of three doses of PEG-rHuMGDF. In the phase 3 study, 64 patients were randomized to receive placebo or the minimally effective dose of PEG-rHuMGDF. The study drug was administered daily starting on the day of bone marrow infusion until the platelet count was greater than or equal to 50 x 10(9)/L (without transfusion) or for a maximum of 28 days. All patients received 10 microg/kg/day filgrastim starting on day 2 until neutrophil count recovery. RESULTS PEG-rHuMGDF appeared to be safe and well tolerated. No significant differences were noted in mortality or disease progression rates. Antibodies to MGDF were not observed. In the phase 1/2 study, the time to platelet recovery to greater than or equal to 20 x 10(9)/L and platelet transfusion requirements were significantly reduced for patients treated with PEG-rHuMGDF compared with placebo (p < 0.05). In the phase 3 study, no significant differences in the kinetics of early thrombopoiesis or platelet transfusions after ABMT were observed. CONCLUSIONS PEG-rHuMGDF was not consistently efficacious in reducing the duration of severe thrombocytopenia. The maximum platelet counts for PEG-rHuMGDF-treated patients occurred a median of 2 weeks after the last dose of drug, suggesting that the biologic effects of this hematopoietic cytokine are delayed compared with other hematopoietic cytokines.

Marginal zone B-cell lymphoma: a retrospective immunophenotypic analysis.

Marginal zone B‐cell lymphoma (MZL) comprises three related yet biologically distinct subtypes—splenic MZL (SMZL), nodal MZL (NMZL), and extranodal MZL of MALT type (MALT). In cases without adequate morphology, immunophenotypic characterization by flow cytometric immunophenotyping (FCI) relies heavily on exclusion of other low‐grade lymphomas. We performed a retrospective review of FCI studies of MZL to search for immunophenotypes specific for MZL and its subtypes. We compared these to follicular lymphoma (FL) as we were specifically interested in differentiating MZL from CD10 negative FL.

Conjunctival lymphocytic infiltrates associated with Epstein-Barr virus

PURPOSE To describe the clinicopathologic features of two patients with Epstein-Barr virus (EBV) associated conjunctival lymphocytic infiltrates. DESIGN Two case reports. METHODS The clinical histories and pathologic findings of two patients with salmon-colored conjunctival infiltrates are described. MAIN OUTCOME MEASUREMENTS Clinical observation and pathologic examination of conjunctival biopsy specimens with accompanying immunohistochemical staining, flow cytometric immunophenotyping, and polymerase chain reaction analysis when appropriate. RESULTS One patient had ipsilateral preauricular lymphadenopathy, elevated serum EBV titers, and a unilateral reactive lymphocytic infiltrate resulting in a conjunctival mass. The other patient had bilateral conjunctival lymphocytic infiltrates causing conjunctival masses. There was an expanded clonal population of B lymphocytes in the conjunctival mass in the second patient. Both patients had EBV antigen in their conjunctival lymphocytic infiltrates. CONCLUSIONS Conjunctival lymphocytic lesions associated with EBV represent a spectrum of reactive infiltrates to monoclonal populations.

T-cell-rich B-cell lymphoma presenting in the spleen: a clinicopathologic analysis of 3 cases.

We review the clinical, pathologic, and molecular genetic features of 3 splenic T-cellrich B-cell lymphomas and discuss their differential diagnosis. All patients presented with symptomatic splenomegaly and underwent diagnostic/therapeutic splenectomy. Microscopically, the spleen in all cases showed a micronodular proliferation of lymphoid cells. A proportion of the nodules demonstrated central hyalinization or sclerosis. There was also an exuberant extramedullary hematopoiesis. On immunohistochemical stain, the nodules consisted predominantly of small T cells with scattered large atypical B cells. The clonal nature of the atypical B cells was confirmed by polymerase chain reaction assays for immunoglobulin heavy-chain gene rearrangement. In the H&E sections, the differential diagnoses included Hodgkins lymphoma, follicular lymphoma, peripheral T-cell lymphoma, and nonneoplastic granulomatous process. The presence of exuberant extramedullary hematopoiesis also raised the possibility of a chronic myeloproliferative disorder. The combined morphologic, immunohistochemical, and molecular genetic data are essential for a correct diagnosis of splenic T-cell-rich B-cell lymphoma.

Sensitivity and specificity of cerebrospinal fluid flow cytometry for the diagnosis of leukemic meningitis in acute lymphoblastic leukemia/lymphoma

Abstract The presence of leukemic blasts detected by light microscopy in cerebrospinal fluid (CSF) establishes the diagnosis of leukemic meningitis in acute lymphoblastic leukemia/lymphoma (ALL). Flow cytometry immunophenotyping (FCI) is a very sensitive method that detects a minute number of aberrant cells, and is increasingly performed on CSF samples. We sought to determine the sensitivity and specificity of CSF FCI for the diagnosis of leukemic meningitis in ALL. Between November 2007 and August 2011, 800 CSF samples from 80 patients with ALL were available from diagnostic lumbar punctures (LPs; n = 80), follow-up LPs (n = 687) and at the time of relapse (n = 33). FCI was performed on 267 samples, and only identified aberrant cells in cytologically confirmed cases of leukemic meningitis. A blinded review of all cases with detectable CSF nucleated cells confirmed these findings. We conclude that CSF FCI has a 100% sensitivity and specificity for the detection of lymphoblasts. However, additional studies are needed to define the role this procedure plays in the diagnosis of leukemic meningitis.