Acute Myeloid Leukemia (AML) With T-Cell Differentiation Arising From Chronic Myelomonocytic Leukemia (CMML).

Chronic myelomonocytic leukemia (CMML) is a myelodysplastic/myeloproliferative neoplasm characterized by peripheral blood monocytosis and bone marrow dysplasia. In approximately one-fourth of cases, CMML can demonstrate progression to acute myeloid leukemia (AML), referred to as AML ex CMML. We present a 58-year-old woman with a past medical history of idiopathic thrombocytopenic purpura (ITP) who demonstrated 24% bone marrow blasts on a repeat biopsy obtained two years after being diagnosed with CMML.

Anakinra versus etoposide-based therapy added to high-dose steroids for the treatment of secondary hemophagocytic lymphohistiocytosis.

Objective: Hemophagocytic lymphohistiocytosis (HLH) is a rare life-threatening, hyperinflammatory syndrome usually treated with high-dose steroids (HDS), often complemented with adjunct therapies, such as etoposide (HLH-94 protocol). Anakinra has been reported to effectively treat HLH; however, has not been comparatively examined with etoposide-based therapies. We sought to evaluate the effectiveness and durability of these treatment approaches.

Role of immunoglobulin heavy and light chain gene rearrangement analysis in differentiating between benign and malignant bone marrow B-cell lymphoid aggregates.

Lymphoid aggregates are found in a minority of bone marrow biopsy and aspirate specimens, and when present, the distinction between benign and malignant aggregates can represent a diagnostic challenge. Morphologic and immunophenotypic evaluation of the aggregates can aid in that distinction but in a few cases, detection of immunoglobulin heavy chain (IGH) and kappa light chain (IGK) gene rearrangements may be needed to rule in or out a malignant disease process. We studied the role of testing for IGH/IGK rearrangements in the distinction between benign and malignant B cell-predominant lymphoid aggregates.

Rare case of leptomeningeal small lymphocytic lymphoma with mutation detected by deep next-generation sequencing.

Involvement of the central nervous system (CNS) is an exceedingly rare presentation of chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), with no consensus on the optimal therapy. Here we describe a 71-year-old man with a skull-base leptomeningeal mass consistent with SLL on biopsy. Malignant cells were observed in the cerebrospinal fluid (CSF), but not in the peripheral blood, bone marrow, or other extramedullary sites.

Infection prevention strategies are highly protective in COVID-19 units while main risks to healthcare professionals come from coworkers and the community.

Background: Early evaluations of healthcare professional (HCP) COVID-19 risk occurred during insufficient personal protective equipment and disproportionate testing, contributing to perceptions of high patient-care related HCP risk. We evaluated HCP COVID-19 seropositivity after accounting for community factors and coworker outbreaks.

Methods: Prior to universal masking, we conducted a single-center retrospective cohort plus cross-sectional study.

Aggressive CD5-Positive Primary Bone Marrow Diffuse Large B-Cell Lymphoma with Leukemic Presentation.

Primary bone marrow diffuse large B-cell lymphoma is an exceedingly rare form of non-Hodgkin lymphoma. It may demonstrate a leukemic presentation, and a proportion of cases have CD5 expression. The prognostic implications of this CD5-positivity remain unknown.

Automated leukocyte parameters are useful in the assessment of myelodysplastic syndromes.

Background: Study utility of seven automated VCS parameters (V-volume, C-conductivity and S-scatter) in leukocytes as an objective read-out of dysplasia in Myelodysplastic Syndromes (MDS).

Methods: Peripheral blood was analyzed by Beckman-Coulter DxH800 hematology analyzer in 43 patients with low-grade, high-grade MDS and 21 control individuals. The differences in mean (MN) and standard deviation (SD) of each parameter were examined.

High-grade B-cell Lymphoma with and Rearrangement Arising from Follicular Lymphoma: Presentation as a Large Peripancreatic Mass.

Follicular lymphoma, the second most common non-Hodgkin lymphoma (NHL), primarily affects adults and shows an indolent clinical course. Rare cases of follicular lymphoma transform to a high-grade B-cell lymphoma with and rearrangements or "double-hit lymphoma". Transformation to a "double-hit lymphoma" portends a worse prognosis and requires aggressive treatment.

A Phase IIa Trial of Metformin for Colorectal Cancer Risk Reduction among Individuals with History of Colorectal Adenomas and Elevated Body Mass Index.

Obesity is associated with risk of colorectal adenoma (CRA) and colorectal cancer. The signaling pathway activated by metformin (LKB1/AMPK/mTOR) is implicated in tumor suppression in Apc mice via metformin-induced reduction in polyp burden, increased ratio of pAMPK/AMPK, decreased pmTOR/mTOR ratio, and decreased pS6/S6 ratio in polyps. We hypothesized that metformin would affect colorectal tissue S6 among obese patients with recent history of CRA.

EBV-Associated Lymphoproliferative Disorders: Update in Classification.

Although about 90% of the world's population is infected by EBV only a small subset of the related infections result in neoplastic transformation. EBV is a versatile oncogenic agent involved in a multitude of hematopoietic, epithelial, and mesenchymal neoplasms, but the precise role of EBV in the pathogenesis of many of the associated lymphoid/histiocytic proliferations remains hypothetical or not completely understood. Additional studies and use of evolving technologies such as high-throughput next-generation sequencing may help address this knowledge gap and may lead to enhanced diagnostic assessment and the development of potential therapeutic interventions.

Crucial role for pathology residents in laboratory self-inspection, a single Institute's experience.

Background: Training in patient safety, quality, and management is a key component of Graduate Medical Education (GME) training in all specialties. However, residency programs, especially Pathology programs, often find it challenging to create strong learning opportunities in these areas.

Objectives: Focused quality assurance (QA) projects are one approach to teach and engage trainees in these key areas.

Epstein-Barr virus incidental expression in bone marrow cells: a study of 230 consecutive bone marrow biopsy samples.

Epstein-Barr virus (EBV) is associated with many neoplastic hematologic conditions, but scattered EBV-positive cells can be detected in lymph nodes of healthy individuals and they usually represent latently infected lymphocytes. The incidence of EBV detection in normal bone marrow samples has not been studied and is largely unknown. The lack of knowledge regarding the true incidence of encountering bystander latent EBV-positive cells in the bone marrow may potentially lead to a diagnostic dilemma when assessing a staging bone marrow for a patient with an EBV-positive B or T/NK-cell lymphoma.

Epstein - Barr virus association with plasma cell neoplasms.

Aims: Epstein-Barr virus (EBV) expression has been reported in several hematopoietic and non-hematopoietic disorders but its expression in plasma cell neoplasms has been largely limited to immunodeficiency-related cases such as in the setting of post-organ transplantation or human immunodeficiency virus (HIV) infection. The aim of this study is to evaluate the association of EBV with plasma cell neoplasms, mainly in immunocompetent patients.

Methods And Results: We retrospectively studied 147 cases of patients with different plasma cell neoplasms (109 plasma cell myelomas, 22 plasmacytomas, and 16 monoclonal gammopathy cases).

Prolymphocytic transformation of lymphoplasmacytic lymphoma: an extremely unusual event.

Although rare cases of prolymphocytic transformation from splenic B-cell lymphomas and follicular lymphoma have been reported, prolymphocytic transformation from lymphoplasmacytic lymphoma has not been previously reported. We report a case of 76-year-old-male patient with a history of Waldenström macroglobulinemia diagnosed in 2010 and treated with infusion chemotherapy. He was in clinical remission for 5 years.

Epstein-Barr virus (EBV)-associated lymphoid proliferations, a 2018 update.

Epstein-Barr virus (EBV) has been linked to many human neoplasms including hematopoietic, epithelial, and mesenchymal tumors. Since our original review of EBV-associated lymphoproliferative disorders in 2007, many advances and developments have been reported. In this review, we will examine the recent advances in EBV-associated lymphoid/histiocytic proliferations, dividing them into reactive, B cell, T/NK cell, immunodeficiency-related, and histiocytic/dendritic cell proliferations.

CD4-Positive T-Cell Primary Central Nervous System Lymphoma in an HIV Positive Patient.

Objectives: Primary central nervous system lymphomas (PCNSLs) in patients with human immunodeficiency virus (HIV) are predominantly B-cell lymphomas associated with Epstein-Barr virus (EBV) and rarely CD8-positive T-cell PCNSLs.

Methods: Patient history, laboratory results, cerebrospinal fluid (CSF), imaging, and brain biopsy specimens were reviewed and tested for T-cell receptor clonality.

Results: A 64-year-old HIV-positive woman sought treatment for lethargy and left-sided weakness.

Differentiating benign from malignant bone marrow B-cell lymphoid aggregates: a statistical analysis of distinguishing features.

Context: Lymphoid aggregates are seen in a minority of bone marrow biopsy specimens, and when present, their neoplastic nature is often apparent by morphologic evaluation. However, the distinction between benign and malignant aggregates can be a diagnostic challenge when there are multiple aggregates with no documented history of lymphoma.

Objective: To aid in the distinction between benign and malignant B-cell lymphoid aggregates.

Thyroid-like follicular carcinoma of the kidney in a young patient with history of pediatric acute lymphoblastic leukemia.

Thyroid-like follicular carcinoma of the kidney (TLFCK) is a rare histological variant of renal cell carcinoma not currently included in the World Health Organization classification of renal tumors. Only 24 previous cases of TLFCK have been reported to date. We report a case of TLFCK in a 19-year-old woman with history of pediatric acute lymphoblastic leukemia.

Human herpesvirus 8-unrelated primary effusion lymphoma-like lymphoma: report of a rare case and review of 54 cases in the literature.

Objectives: To report a patient with primary effusion lymphoma who was negative for human herpesvirus-8 (HHV-8), human immunodeficiency virus, Epstein-Barr virus, hepatitis C virus, and hepatitis B virus, as well as review 54 reported cases of HHV-8-unrelated primary effusion lymphoma (PEL)-like lymphoma in the literature to clarify the nature of this entity.

Methods: The patients' characteristics, clinical presentation, pathogenesis, morphologic-immunophenotypic features, clinical management, and prognosis were studied.

Results: HHV-8-negative PEL-like lymphomas often occur in immunocompetent and elderly patients, are sometimes associated with chronic inflammation-related fluid overload, are mostly large B-cell or large B-cell with plasmacytic differentiation type, and are associated with a better prognosis.

Follicular dendritic cells: origin, function, and different disease-associated patterns.

Follicular dendritic cells (FDCs) are a specialized type of antigen-presenting dendritic cells that are largely restricted to lymphoid follicles. They form dense three-dimensional meshwork patterns within benign follicles, which maintain the follicular architecture. The FDC function is to bind and retain antigens by linking to complement and immune complexes and then present these antigens to germinal center B cells that start the secondary immune response.

Benign lymphoid aggregates in the bone marrow: distribution patterns of B and T lymphocytes.

Benign lymphoid aggregates are seen in only a minority of bone marrow specimens, but their distinction from non-Hodgkin lymphoma, particularly B-cell lymphomas, can represent a diagnostic challenge. Although criteria have been proposed to help distinguish between benign and malignant aggregates, a detailed description of the distribution patterns of B and T lymphocytes within benign lymphoid aggregates has not been investigated. One hundred thirty-seven cases of bone marrow specimens containing benign aggregates were studied with a panel of immunostains.

Extraosseous plasmacytoma with an aggressive course occurring solely in the CNS.

Extraosseous (extramedullary) plasmacytoma is a relatively indolent neoplasm that constitutes 3-5% of all plasma cell neoplasms. Rare cases have been reported to truly occur in the CNS and not as an extension from a nasal lesion. EBV expression in plasma cell neoplasms has been reported in very few cases that are mainly post-transplant or occurring in severely immunosuppressed patients.