Determination of age-dependent bone marrow normocellularity.

Objectives: Determination of bone marrow cellularity is a key part of bone marrow examination because it provides a small window into a patient's current state of hematopoietic well-being. Traditionally, bone marrow cellularity is estimated semiquantitatively through microscopic examination of core biopsy specimens harvested from the iliac crest of the pelvic bone. Bone marrow cellularity is then designated as hypercellular, normocellular, or hypocellular based on the patient's age.

Therapy-related acute lymphoblastic leukemia without 11q23 abnormality: report of six cases and a literature review.

Therapy-related acute lymphoblastic leukemia (t-ALL) is a rare secondary leukemia following chemotherapy and/or radiotherapy for primary malignancies. Chromosomal 11q23 abnormality, frequently detected in therapy-related acute myeloid leukemia, is the most common cytogenetic alteration in t-ALL. However, t-ALL cases without 11q23 abnormality have been rarely described.

Aberrant expression of CD7 in myeloblasts is highly associated with de novo acute myeloid leukemias with FLT3/ITD mutation.

Acute myeloid leukemia (AML) with normal cytogenetics represents approximately 40% to 50% of de novo AML. This heterogeneous AML subgroup constitutes the single largest cytogenetic group with an intermediate prognosis. Previous studies have suggested that the Fms-like tyrosine kinase-3 internal tandem duplication (FLT3/ITD) mutation-positive de novo AML may represent a distinctive subgroup of AML.

Clinical and pathologic analysis of 16 cases of relapsed chronic myeloid leukemia after stem cell transplantation.

Chronic myeloid leukemia (CML) is a myeloproliferative disease that originates in an abnormal pluripotent bone marrow stem cell and is characteristically associated with the Philadelphia chromosome and/or the bcr/abl fusion gene. Despite the exciting success of the bcr/abl tyrosine kinase-specific inhibitor imatinib for CML treatment, hematopoietic stem cell (bone marrow or peripheral blood stem cell) transplantation (HCT) remains the only "curative" approach for the majority of patients. Although HCT outcomes for patients with CML have improved considerably during the past 2 decades, relapse after HCT may occur.

An aggressive extranodal NK-cell lymphoma arising from indolent NK-cell lymphoproliferative disorder.

Indolent NK-cell lymphoproliferative disorder, also known as chronic natural killer (NK) cell large granular lymphocytosis (leukemia), is a very rare entity in the World Health Organization (WHO) Classification of Tumors of Hematopoietic & Lymphoid Tissues. Unlike aggressive NK-cell leukemia, which is malignant, the WHO does not specify whether indolent NK-cell lymphoproliferative disorder is reactive or neoplastic. Patients with indolent NK-cell lymphoproliferative disorder are usually asymptomatic older adults who have a nonprogressive, very stable clinical course.

KSHV/HHV8-associated lymphoma simulating anaplastic large cell lymphoma.

We report a unique, previously undescribed case of KSHV/HHV8-associated lymphoma in a 49-year-old HIV-seropositive patient. The cervical lymph node-based lymphoma displayed distinctive characteristic features of preferential sinusoidal infiltrate and anaplastic cellular morphology, closely resembling classic anaplastic large cell lymphoma of the WHO classification both histologically and immunophenotypically. Paraffin immunohistochemical study showed that the lymphoma cells were strongly positive for KSHV/HHV8 latency-associated nuclear antigen, and PCR analysis confirmed the presence of KSHV/HHV8 infection.

Histiocytic lesions involving the bone marrow.

Histiocytic lesions involving the bone marrow include a number of reactive and neoplastic disorders. This article discusses the morphologic, immunophenotypic, and genotypic features of a variety of diseases associated with histiocytes and/or monocytes. Lysosomal storage disorders and hemophagocytic syndromes are often first diagnosed by bone marrow examination.