Definition Nodal marginal zone lymphoma (NMZL) is a primary nodal B-cell neoplasm derived from post–germinal center B cells. This lymphoma shares morphologic and immunophenotypic similarities with other marginal zone lymphomas, particularly extranodal marginal zone lymphoma (EMZL) of mucosa-associated lymphoid tissue…
Primary cutaneous B-cell lymphomas (CBCLs) are a heterogeneous group of B-cell lymphomas that present in the skin without evidence of extracutaneous disease at the time of diagnosis. CBCLs are much less common than primary cutaneous T-cell lymphomas (CTCLs). In Western…
In classifying non-Hodgkin's lymphomas, considerable attention has been paid to architectural, cytologic, and functional similarities among the various lymphomas and normal lymphoid tissue, exemplified by the peripheral lymph node. However, studies of extranodal lymphomas, particularly gastrointestinal lymphomas (accounting for the…
Definition Follicular lymphoma (FL) is defined in fourth edition of the WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues as a neoplasm composed of follicle center (germinal center) B cells (typically both centrocytes and centroblasts) that usually has at…
Definition The term splenic marginal-zone lymphoma (SMZL) was coined by Schmid and colleagues in 1992 for a B-cell lymphoma involving the spleen and bone marrow characterized by a micronodular tumoral infiltration that replaces the preexisting lymphoid follicles and shows marginal-zone…
Definition of Disease and Nomenclature Hairy cell leukemia (HCL) is a mature B-cell neoplasm that involves primarily the blood, bone marrow, and splenic red pulp. The neoplastic lymphocytes have surface “hairy” projections and express the B-cell–associated antigens CD19, CD20, and…
Definition of Disease Lymphoplasmacytic lymphoma (LPL) is defined in the WHO Classification of Tumours of Haematopoetic and Lymphoid Tissues, fourth edition, as a small B-cell neoplasm composed of lymphocytes, plasma cells, and plasmacytoid lymphocytes, which does not meet criteria for…
B-Cell Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma (B-CLL/SLL) Definition of Disease B-cell chronic lymphocytic leukemia (B-CLL) is a clonal disorder of mature B lymphocytes, which are characterized by small, round nuclei; highly condensed chromatin; inconspicuous nucleoli; scant cytoplasm; and unique immunophenotype.…
Historical Background The classification of lymphoid neoplasms used in this text is the one published by the World Health Organization (WHO) in WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues . Initially published in 2008, the WHO's fourth edition…
This chapter addresses the peripheral blood and bone marrow response to a variety of non-malignant conditions. A bone marrow examination may be performed to evaluate a fever of unknown origin, looking for a specific infectious cause. In inflammatory or metabolic…