Shereen Gheith

Percentage of γδ T Cells in Panniculitis by Paraffin Immunohistochemical Analysis

Cutaneous T-cell lymphomas with panniculitis-like histologic features have different clinical courses depending on whether they are composed of alphabeta T cells or gammadelta T cells, necessitating their distinction for proper prognostication. However, unlike alphabeta T cells, gammadelta T cells cannot be reliably detected in formalin-fixed, paraffin-embedded sections. We demonstrated that a commercially available antibody can detect gammadelta T cells and examined 2 cases of flow cytometry-proven gammadelta T-cell lymphomas and 15 control cases of nonneoplastic panniculitis. In both lymphomas, the atypical lymphocytes were gammadelta T cells, whereas the reactive lymphocytes were alphabeta T cells. In contrast, nonneoplastic panniculitis had predominantly alphabeta T cells with many fewer and individually scattered gammadelta T cells. The detection of gammadelta T cells in paraffin sections provides a powerful new tool to characterize T cells in lymphomas and inflammation.

Immunotherapy-Associated Hemolytic Anemia with Pure Red-Cell Aplasia

The authors report a case of immunotherapy-associated autoimmune hemolytic anemia with pure red-cell aplasia in a patient receiving the anti–PD-1 antibody pembrolizumab for therapy of mucosal malig...

Flow Cytometric Quantitation of Natural Killer Cells and T Lymphocytes Expressing T-Cell Receptors Alpha/Beta and Gamma/Delta is Not Helpful in Distinguishing Benign From Malignant Body Cavity Effusions.

Quantitation of natural killer (NK) cells in benign and malignant effusions has yielded conflicting results in the past. Studies have claimed higher, lower, and essentially equal percentages of NK cells for benign and malignant effusions. In addition, virtually no literature exists on the numbers and distribution of T lymphocytes expressing T‐cell receptor alpha/beta (TCR α/β) and T‐cell receptor gamma/delta (TCR γ/δ) in body effusions.

Flame Cell in IgA Monoclonal Gammopathy of Undetermined Significance.

![Figure][1] A 56-year-old diabetic woman presented with significant proteinuria. Serum protein electrophoresis demonstrated an elevated α2 region. Immunofixation confirmed immunoglobulin A-λ (IgA-λ) monoclonal protein (unquantifiable). The serum IgA level was 763 mg/dL (normal range, 83-

Immunoblastic follicular lymphoma: a very unusual transformation of low-grade follicular lymphoma.

A 73-year-old man, in clinical remission 17 years after radiation therapy for a localized low-grade follicular lymphoma (FL), developed extensive lymphadenopathy, ascites, and splenomegaly with splenic masses. Axillary lymph node biopsy showed FL composed of nodules of centrocytes side by side with nodules of immunoblasts rather than centroblasts. Immunophenotyping revealed conventional FL markers (BCL-2, BCL-6, and CD10) as well as MUM-1 in the immunoblastic component, suggesting postgerminal center differentiation. Fluorescence in situ hybridization showed t(14;18) in both centrocytic and immunoblastic components and a copy gain of BCL-6 predominantly in the immunoblastic component. Areas of centrocytic and of immunoblastic nodules were macrodissected separately and underwent molecular evaluation for immunoglobulin heavy chain gene rearrangement. Identical base-pair peaks were found, attesting to their clonal identity. This case represents a very unusual example of transformation of a low-grade FL to a nodular immunoblastic FL.

Primary dural lymphoblastic B-cell lymphoma: a rare subtype of aggressive dural lymphoma

Lymphomas arising in the dura mater represent a rare subset of primary central nervous system lymphoma (PCNSL). The majority of primary dural lymphoma (PDL) are low-grade marginal zone lymphomas (MZL) characterized by an indolent course and favorable long-term outcomes. Primary aggressive dural lymphomas are exceedingly rare with a paucity of cases reported in the literature. Herein, we describe a case of primary lymphoblastic dural lymphoma. To our knowledge, this is the second report of an isolated dural B-lymphoblastic lymphoma (B-LBL) in an immunocompetent patient.

Rituximab-Induced Splenic Rupture and Cytokine Release.

Patient: Female, 55 Final Diagnosis: Mantle cell lymphoma Symptoms: Cytokine release syndrome • hypoglycemia • hypotension • splenic rupture • splenomegaly • vision loss Medication: — Clinical Procedure: Case Report Specialty: Oncology Objective: Unusual clinical course Background: Rituximab is a therapeutic monoclonal antibody that is used for many different lymphomas. Post-marketing surveillance has revealed that the risk of fatal reaction with rituximab use is extremely low. Splenic rupture and cytokine release syndrome are rare fatal adverse events related to the use of therapeutic monoclonal antibodies, especially in aggressive malignancies with high tumor burden. Case Report: A 55-year-old woman presented with abdominal pain and type B symptoms and was diagnosed with mantle cell lymphoma. Initial peripheral blood flow cytometry showed findings that mimicked features of chronic lymphocytic leukemia. Further treatment with rituximab led to catastrophic treatment complications that proved to be fatal for the patient. Conclusions: Severe cytokine release syndrome associated with biologics carries a very high morbidity and case fatality rate. With this case report we aim to present the diagnostic challenge with small B-cell neoplasms, especially mantle cell lymphoma and chronic lymphocytic lymphomas, and underscore the importance of thorough risk assessment for reactions prior to treatment initiation.