Late-onset bexarotene-induced CD4 lymphopenia in a cutaneous T-cell lymphoma patient.

Various infections, autoimmune diseases, medications, and total-body irradiation are known factors associated with CD4 lymphopenia, defined as a CD4 T-cell count below 300 cells/mL or less than 20% of total lymphocytes. We report a rare case of a patient with cutaneous T-cell lymphoma (CTCL) who developed profound CD4 lymphopenia in the setting of long-term bexarotene therapy. Bexarotene is a third-generation retinoid that inhibits epithelial cell proliferation and is approved for treatment of advanced CTCL (stages IIB-IVB) in adult patients who have failed at least 1 prior systemic therapy.

Richter transformation with c-MYC overexpression: report of three cases.

Pathogenesis of Richter transformation (RT) or Richter syndrome (RS) of chronic lymphocytic leukemia (CLL) is still largely unknown. Increasing evidences show that c-MYC may play a role in the development of RS. Here we report three cases of RS with overexpression of c-MYC.

The RUNX2 Transcription Factor Negatively Regulates SIRT6 Expression to Alter Glucose Metabolism in Breast Cancer Cells.

Activation of genes promoting aerobic glycolysis and suppression of mitochondrial oxidative phosphorylation is one of the hallmarks of cancer. The RUNX2 transcription factor mediates breast cancer (BC) metastasis to bone and is regulated by glucose availability. But, the mechanisms by which it regulates glucose metabolism and promotes an oncogenic phenotype are not known.

Imbalanced matriptase pericellular proteolysis contributes to the pathogenesis of malignant B-cell lymphomas.

Membrane-associated serine protease matriptase is widely expressed by epithelial/carcinoma cells in which its proteolytic activity is tightly controlled by the Kunitz-type protease inhibitor, hepatocyte growth factor activator inhibitor (HAI-1). We demonstrate that, although matriptase is not expressed in lymphoid hyperplasia, roughly half of the non-Hodgkin B-cell lymphomas analyzed express significant amounts of matriptase. Furthermore, a significant proportion of these tumors express matriptase in the absence of HAI-1.

Pediatric presentation of splenic marginal zone lymphoma on FDG PET/CT scan.

Splenic marginal zone lymphoma (SMZL) comprises about 1% of B-cell lymphomas and typically occurs after the age of 50 years. Pediatric SMZL is very rare, and no FDG PET/CT imaging of the disease has been reported. In the current study, a 4-year-old boy with biopsy-proven SMZL had FDG PET/CT for staging, which showed increased metabolic activity in the spleen and left cervical lymph nodes.

Amplified RPS6KB1 and CDC2 genes are potential biomarkers for aggressive HIV+/EBV+ diffuse large B-cell lymphomas.

RPS6KB1 encodes p70S6K/p85S6K, which plays a role in the PI3K/Akt/mTOR signal transduction pathway. CDC2 gene encodes cdc2, which is critical for G2/M cell cycle progression. We had previously shown that amplified RPS6KB1 and CDC2 are commonly detected in the EBV+ diffuse large B-cell lymphoma (DLBCL) in HIV patients.

c-Myc and E2F1 drive PBK/TOPK expression in high-grade malignant lymphomas.

c-Myc has been implicated in a variety of hematologic malignancies including Burkitt's lymphoma. Targeting c-Myc driven growth pathways could be therapeutically useful but might require the identification of critical downstream proteins. Here we show that the serine-threonine kinase PBK/TOPK is frequently overexpressed in high-grade lymphomas and its expression is positively correlated to that of c-Myc and E2F1.

Tertiary center referral patterns for patients with myelodysplastic syndrome are indicative of age and race disparities: a single-institution experience.

Little is known about disparities in myelodysplastic syndromes (MDS). We performed a retrospective chart review of patients with MDS (n = 252) evaluated at the University of Maryland Greenebaum Cancer Center between 2000 and 2010. The median age at diagnosis was 65 years, which was lower than the median age of 76 years for patients with MDS in the Surveillance, Epidemiology and End Results database.

Diagnosis of biphenotypic acute leukemia: a paradigmatic approach.

Biphenotypic acute leukemia (BAL), or acute leukemia with a single population of blasts coexpressing markers of two different lineages, is a rare clinical entity. To define BAL, a scoring system was proposed by the European Group of Immunological Markers for Leukemias (EGIL) in 1995. However, increasing evidence suggests that this system has limitations, as acknowledged by the 2008 World Health Organization (WHO) Classification of Tumors of Hematopoietic and Lymphoid Tissues.

Pitfalls in diagnostic hematopathology -- Part II.

The overlapping features of malignant lymphomas create a diagnostic "grey zone" , and lead to the invention of "grey zone lymphomas". There are several major grey zone lymphomas: 1) Lymphomas with overlapping features of Hodgkin lymphoma and large B-cell lymphoma; 2) Lymphomas with overlapping features of Burkitt lymphoma and diffuse large B-cell lymphoma; 3) Lymphomas with overlapping features of nodular lymphocyte predominant Hodgkin lymphoma and T-cell/histiocyte rich large B-cell lymphoma; 4) Lymphomas with overlapping features of Hodgkin lymphoma, anaplastic large cell lymphoma (ALCL) and peripheral T-cell lymphoma (PTCL); 5) T-cell classical Hodgkin lymphoma and ALCL-HL. The second review of this series will be dedicated to discussion of the "grey zone" features of the lymphomas and how to narrow down the "grey zone" between those lymphomas.

Phospho-p70S6K and cdc2/cdk1 as therapeutic targets for diffuse large B-cell lymphoma.

p70S6K/p85S6K and cdc2/cdk1 are members of the serine/threonine protein kinase family. p70S6K/p85S6K is one of the downstream effectors of the PI3K/Akt/mTOR signal transduction pathway. It phosphorylates S6 protein of 40S ribosomal subunit and thus functions in protein synthesis and cell growth.

Follicular lymphoid hyperplasia of the palate: case report and literature review.

Follicular lymphoid hyperplasia (FLH) of the palate is a very rare benign, proliferative process, with only 20 cases published so far in the English language literature. We describe a case, in a 55-year-old Caucasian female, who developed a swelling in the left posterior hard palate. Bony involvement was absent.

Fatal subcutaneous panniculitis-like T-cell lymphoma gamma/delta subtype (cutaneous gamma/delta T-cell lymphoma): report of a case and review of the literature.

Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a distinct type of peripheral T-cell lymphoma, which has gained recognition over the past decade. The disease presents complex clinical, pathologic, and immunohistochemical features, which warrant awareness by dermatologists, dermatopathologists, hematopathologists, hematologists, oncologists, and internists. SPTCL was initially included as a provisional entity in the Revised European-American Lymphoma classification, followed by the European Organization for Research and Treatment of Cancer classification as a primary cutaneous lymphoma, and subsequently as a distinct entity by the World Health Organization classification.

Pitfalls in diagnostic hematopathology: part I.

Pitfalls in diagnostic hematopathology are underestimated and underreported. Major causes of diagnostic error in hematopathology include: 1) inadequate material; 2) inadequate workup; 3) inadequate clinical correlation; 4) over or under interpretation; 5) challenges in hematopathology. In the first part of this review series, I will focus on the pitfalls in diagnosing and differentiating chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) and mantle cell lymphoma, and discuss the strategies to avoid potential diagnostic errors based on my personal experience.

C-MYC rearrangements are frequent in aggressive mature B-Cell lymphoma with atypical morphology.

Diagnosis and classification of aggressive mature B-cell lymphoma with atypical morphology remains a challenge. To identify factors that may contribute to the atypical morphology, we selected eight such cases and evaluated their morphologic, immunophenotypic and cytogenetic features and clinical outcomes. The neoplastic cells showed a diffuse monotonous infiltrating pattern with a spectrum of morphology including: 1) L1 lymphoblastic; 2) centroblastic; 3) immunoblastic; and 4) mixed centroblastic and immunoblastic.

Myeloid sarcomas: a histologic, immunohistochemical, and cytogenetic study.

Context: Myeloid sarcoma (MS) is a neoplasm of immature granulocytes, monocytes, or both involving any extramedullary site. The correct diagnosis of MS is important for adequate therapy, which is often delayed because of a high misdiagnosis rate.

Objective: To evaluate the lineage differentiation of neoplastic cells in MS by immunohistochemistry, and to correlate the results with clinicopathologic findings and cytogenetic studies.