The development of a second haematological disease during the course of systemic mastocytosis is a well-known phenomenon. In most of the cases, they consist of myelodysplasia or myeloproliferative disorders. The association with lymphoproliferative disorders has also been described, but it is uncommon and the relationship is not well established. We report a patient diagnosed with systemic mast...

The BCR-ABL1-negative classic myeloproliferative neoplasms, polycythemia vera (PV), essential thrombocytemia (ET) and primary myelofibrosis are clonal stem cell disorders associated with an increased production of mature blood cells belonging preferentially to one cell linage. They share substantial phenotypic mimicry, can undergo phenotypic shifts (from PV to ET and vice versa) as well as evol...

Myeloproliferative disorders are variable disorders, based on the genetic abnormality present and the cell line progenitors that are affected. In this case, we discuss a novel gene translocation in the subset of PDGFRB mutations, first seen with prominent hyperbasophilia. This case demonstrates the possibility for lower therapeutic doses of imatinib mesylate than previously reported, in order t...

Atypical cellular disorders are commonly considered part of the gray zone linking oncology to hematology and immunology. Although these disorders are relatively uncommon, they often represent significant clinical problems, provide an opportunity to understand basic disease mechanisms, and serve as model systems for the development of novel targeted therapies. This chapter focuses on such disord...

BACKGROUND AND OBJECTIVES The JAK2 V617F tyrosine kinase mutation is present in the great majority of patients with polycythemia vera (PV), and approximately half of the patients with essential thrombocythemia (ET) and primary myelofibrosis (PMF). The three distinct disease entities may be considered as three phenotypic presentations of the same JAK2 V617F positive chronic myeloproliferative di...

Systemic mast cell disease (SMCD) cannot be distinguished from reactive mastocytosis (RM) by quantitation of mast cells in aspirate smears, and few studies have analyzed systematically the morphologic features of mast cells in SMCD vs RM. In addition, although SMCD is associated with myeloproliferative disorders/myelodysplastic syndromes (MPD/MDS), it is not known whether subtle signs of dyspla...