title: Hypereosinophilic syndrome: lymphoproliferative and myeloproliferative variants.
abstract: Idiopathic hypereosinophilic syndrome is a largely heterogeneous disorder defined as persistent, marked hypereosinophilia of unknown origin complicated by end-organ damage. Recent research in cellular and molecular biology has led to the characterization of distinct underlying hematological disorders, primitively involving cells of the myeloid or lymphoid lineage. The ability to classify many hypereosinophilic syndrome patients on the basis of pathogenesis of hypereosinophilia has radically changed therapeutic perspectives. Indeed, imatinib mesylate has become first-line therapy for patients in whom the FIP1L1-PDGFRalpha fusion gene is detected, whereas corticosteroids remain the mainstay for management of patients in whom hypereosinophilia is secondary to the overproduction of interleukin 5 by abnormal T-cells. Use of monoclonal anti-interleukin-5 antibodies in the latter group of patients has a strong rationale and could decrease cumulative corticosteroid doses and toxicity. As far as prognosis of these disease variants is concerned, hypereosinophilic syndrome patients with the FIP1L1-PDGFRalpha fusion gene may develop acute myelogenous (eosinophilic) leukemia, whereas those with clonal interleukin-5-producing T-cells have an increased risk of developing T-cell lymphoma. It is currently unclear whether timely therapeutic intervention in such patients could interfere with long-term progression toward malignant hematological disorders.
authors.affiliation: Department of Internal Medicine-Erasme Hospital, Brussels, Belgium. froufoss@ulb.ac.be
authors.forename: Florence
authors.initials: F
authors.lastname: Roufosse
authors.forename: Michel
authors.initials: M
authors.lastname: Goldman
authors.forename: Elie
authors.initials: E
authors.lastname: Cogan
mesh_terms: D000911:Antibodies, Monoclonal / Q000627:therapeutic use; D015703:Antigens, CD / Q000276:immunology; D000951:Antigens, Neoplasm / Q000276:immunology; D000970:Antineoplastic Agents / Q000627:therapeutic use; D001549:Benzamides; D000074301:CD52 Antigen; D005938:Glucocorticoids / Q000627:therapeutic use; D006023:Glycoproteins / Q000276:immunology; D006801:Humans; D017681:Hypereosinophilic Syndrome / Q000145:classification* / Q000175:diagnosis* / Q000188:drug therapy; D000068877:Imatinib Mesylate; D007155:Immunologic Factors / Q000627:therapeutic use; D015848:Interleukin-5 / Q000096:biosynthesis / Q000276:immunology; D008232:Lymphoproliferative Disorders / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology; D009196:Myeloproliferative Disorders / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology; D015514:Oncogene Proteins, Fusion / Q000235:genetics; D010879:Piperazines / Q000627:therapeutic use; D011379:Prognosis; D011743:Pyrimidines / Q000627:therapeutic use; D020796:Receptor, Platelet-Derived Growth Factor alpha / Q000235:genetics; D039221:mRNA Cleavage and Polyadenylation Factors / Q000235:genetics
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D000951:Antigens, Neoplasm; D000970:Antineoplastic Agents; D001549:Benzamides; D000074301:CD52 Antigen; C000613862:CD52 protein, human; D005938:Glucocorticoids; D006023:Glycoproteins; D007155:Immunologic Factors; D015848:Interleukin-5; D015514:Oncogene Proteins, Fusion; D010879:Piperazines; D011743:Pyrimidines; D039221:mRNA Cleavage and Polyadenylation Factors; D000068877:Imatinib Mesylate; C479819:FIP1L1-PDGFRA fusion protein, human; D020796:Receptor, Platelet-Derived Growth Factor alpha