More than 150 years ago, Thomas Hodgkin described several cases of a lymphoproliferative disease, later named Hodgkin disease. For a long time this malignancy, now called Hodgkin lymphoma (HL), has been one of the most enigmatic forms of lymphomas. This…
Introduction and Historical Background The classification of malignant lymphomas has undergone significant changes over the past 50 years. The current approach is based on the integration of morphologic, phenotypic, genetic, and clinical features that allows the identification of distinct disease…
Hairy cell leukemia (HCL) is one of the diseases exemplifying the importance of the application of appropriate diagnostic techniques and the importance of treatment strategies to obtain the best treatment outcomes for the individual patient. The disease was first described…
Over the past several years, major advances have been realized in terms of improved understanding of the pathophysiology and therapeutic options for chronic lymphocytic leukemia (CLL). The plethora of information about CLL has increased dramatically and made management of what…
Paul Ehrlich used his 1878 doctoral thesis to characterize a new cell type—the mast cell (MC)—based on its reactivity to aniline dyes and the metachromatic appearance of its cytoplasmic granules. He referred to MCs as Mastzellen and he speculated that…
Eosinophils are highly specialized granulocytic effector cells that produce and store numerous biologically active mediators, including cytotoxic proteins, lipid mediators, chemotactic peptides, and cytokines ( Table 74.1 ). Under various pathologic conditions, blood eosinophils transmigrate through the endothelial layer and…
Myelodysplastic syndrome (MDS)/myeloproliferative neoplasm (MPN) overlap syndromes are a group of rare myeloid malignancies that paradoxically exhibit both dysplastic and proliferative hematopoietic cell characteristics. They share phenotypic features of both MDS, such as dysplasia and cytopenias, and of MPNs, including…
Primary myelofibrosis (PMF) is a Philadelphia chromosome-negative, clonal, myeloproliferative neoplasm (MPN) that is often but not always accompanied by the driver mutations JAK2V617F , calreticulin exon 9 ( CALR ), and the thrombopoietin receptor, MPL515L/K . PMF is clinically characterized…
Essential thrombocythemia (ET) is a chronic myeloproliferative neoplasm (MPN) characterized by platelet counts in excess of 450 × 10 9 /L, profound bone marrow (BM) megakaryocyte hyperplasia, leukocytosis, splenomegaly, a clinical course punctuated by hemorrhagic and/ or thrombotic episodes, and…
Under normal conditions, the red blood cell (RBC) mass in humans is tightly controlled and remains relatively constant in a given individual. The numbers of senescent RBCs lost daily are replaced by newly formed ones by a carefully controlled network…