title: The 2016 revision of WHO classification of myeloproliferative neoplasms: Clinical and molecular advances.
abstract: Clinical evidence supports the need of changing the diagnostic criteria of the 2008 updated WHO classification for polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF). In JAK2-mutated patients who show characteristic bone marrow (BM) morphology, clinical studies demonstrated that a hemoglobin level of 16.5g/dL in men and 16.0g/dl for women or a hematocrit value of 49% in men and 48% in women are the optimal cut off levels for distinguishing JAK2-mutated ET from "masked/prodromal" PV. Therefore BM morphology was upgraded to a major diagnostic criterion. Regarding ET the key issue was to improve standardization of prominent BM features enhancing differentiation between "true" ET and prefibrotic/early primary myelofibrosis (prePMF). These two entities have shown a different epidemiology and clinical outcomes. Concerning prePMF a more explicit clinical characterization of minor criteria is mandated for an improved distinction from ET and overt PMF and accurate diagnosis and outcome prediction.
authors.affiliation: Research Foundation, Papa Giovanni XXIII Hospital, Bergamo, Italy. Electronic address: tbarbui@asst-pg23.it.
authors.forename: T
authors.initials: T
authors.lastname: Barbui
authors.affiliation: Institute of Pathology, University of Cologne, Cologne, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Thiele
authors.affiliation: Division of Hematology and Blood Coagulation, Department of Internal Medicine I, Medical University of Vienna, Vienna, Austria.
authors.forename: H
authors.initials: H
authors.lastname: Gisslinger
authors.affiliation: Division of Hematology, Papa Giovanni XXIII Hospital, Bergamo, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Finazzi
authors.affiliation: Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy.
authors.forename: A M
authors.initials: AM
authors.lastname: Vannucchi
authors.affiliation: Division of Hematology, Mayo Clinic, Rochester, MN, USA.
authors.forename: A
authors.initials: A
authors.lastname: Tefferi
mesh_terms: D004198:Disease Susceptibility; D006801:Humans; D009196:Myeloproliferative Disorders / Q000175:diagnosis* / Q000209:etiology; D017410:Practice Guidelines as Topic; D014944:World Health Organization
keywords: Clinical aspects; Essential thrombocythemia; Overt primary myelofibrosis; Polycythemia vera; Prefibrotiy/early primary myelofibrosis; Revision